Temple Thorold Turning 1867

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ROUTLEDGE'S JF--/'li{

EVERY BOY'S ANNUAL.

AN ENTERTAINING

l\t,tisnUnnu nf Q9rigimd JHerntun.

EDITED BY EDMUND ROUTLEDGE.

Bitb illustrations.

LONDON:

GEORGE ROUTLEDGE AND 'SONS,

THE BRO.!DW.!Y, LUDGATE ;

NEW YORK: 416, BROOME STREET.

1867.

© 2013 The Toolemera Press - www.toolemera.com

COX AND WYMAN,

ORIENTAL, CLASSICAL, AND GENERAL l'RINTERS, GREAT QUEEN STREET,

LINCOLN'S-INN FIELDS, LONDON, W.C.


C 0 NT ENT S.

PAGE

BARFORD BRIDGE; OR, SuHOOLBOY TRIALS. By the Rev •.

H. C . Adams, M.A.

1, 65, 129, 232, 257, 321, 385, 449, 544, 577, 676, 705

CrrEss • 19, 106, 147, 204, 275, 378, 433, 468, 523, 636, 663, 755

WORDS WHICH HAVE A HISTORY. By the Rev. Frederic W.

Farrar, M.A. . . . . . . . . . . . . . 24, 82, 171

THE LATHE, AND How TO u SE IT ; OR, THE PRINCIPLES AND

PRACTICE OF PLAIN TURNING. By Temple Thorold.

31, 96, 161, 224, 735

SToDARE's FLY-NOTES; OR, CONJURING MADE EAsY FOR J uvE-

NILE AMATEURS. By Colonel Stodare.

41, 87, 182, 280, 358, 438

JACK-OF-ALL-TRADES. By Thomas Miller.

52, 117, 153, 209, 289, 367, 404, 496, 513, 615, 641, 723

CHARADES, REBUSES, ETC. • • • • • • 60, 123, 190

OPEN THE WINDOW, AND OLEAN UP. By R. M. Ballantyne • 111

ANSWERS TO CHARADES, REBUSES, ETC. • • • • • 128, 160, 254

RECOLLECTIONS OF HARROW. By an Old Harrovian.

178, 216, 300, 341, 485, 529, 594, 656, 756

REGINALD w ARRENDER ; OR, EARLY DAYS AT ETON. By

William H. G. Kingston • • • • • • • • 193, 306, 346


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[To face Pug.e 31.


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31

THE LATHE, .AND HOW TO USE IT·;

OR,

THE PRINCIPLES AND PRACTICE OF PLAIN TURNING.

B Y TE M P L E T H 0 R 0 L D.

CHAPTER 1.-THE LATHE.

HAT could we do without the lathe or its combinations ? Wh~t could James Watt and his followers have done without its aid 1 From ah engineering point of view,, we think we may safely answer, nothing.

If the turner's art were unknown, mechanical science, as a practical, realizable fact, could scarcely exist. The

steam-engine would only be a wonderful something that worked beauti~ fully in theory, and would be sure to do so in practice, if the parts that required to be round could but be made truly circular.

So unfortunate a state of things, happily for us, does not exist ; if it did, you may be quite sure, printing by machinery would be unknown, ·and that you could not buy ROUTLEDGE's MAGAZINE FOR BOYS for four~ pence, or. even for three times fourpence.

The lathe is of very ancient origin. Pliny ascribes the invention of the turner's craft to Theodore of Samos, and refers to one Thericles who was celebrated as a skilled turner. The ancients were in the habit of saying, it must have been formed in the lathe, when speaking of the work-, manship of any object that was wrought with great delicacy and accuracy.

In the Old Testament we find mention of the potter's wheel, which, in principle, is closely allied to the lathe ; but the spindle or mandrel of the former is held in a vertical instead of a horizontal position, as in the latter.

The simplest form of lathe that can be employed, for turning objects which are to be wrought only on the outside, is the pole-latlie, which consists simply of two horizontal centres, fixed exactly opposite each other, in suitable supports of either metal or wood. One of the supports is permanently secured to a bench or table, but the other is movable,


32 THE LATHE, AND HOW TO USE IT j OR,

and can be fixed temporarily at the proper distance from its fellow, the distance being determined by the length of the object to be turned. The object or work is suspended between the centres, which penetrate a little way into its extremities, in order to hold it firmly, at the same time allowing it to rotate freely on its axis. Motion is imparted to the

. work by means of a gut or line, which is coiled round it a few times near one end. The upper extremity of the line is fastened to an elastic pole or lath overhead, and the lower end is secured to a treadle or footboard, or is simply formed into a loop for the workman's foot. The action is very simple, and may easily be understood. When the operator depresses the treadle, the line which is coiled round the work unwinds in favour of the lower length, but the upper length is shortened by the same amount, thereby causing the work to revolve. This action draws clown the elastic pole or lath, which, when the workman raises his foot, returns to its former position, and causes the work to rotate in the opposite direction. A rest or support for the cutting tool is secured to the bench at a convenient distance from the work, and slightly below the centre.

When the work is set in motion by depressing the treadle, it must revolve towar els the rest, and on firmly holding a suitable tool thereon, and applying its edge to the revolving work, the prominences of the latter may gradually be removed, until a truly circular form is obtained. As the work rotates in the opposite direction when the foot is raised, the edge of the tool must be slightly withdrawn, otherwise its edge would be injured. This alternate backward and forward motion is inconvenient, and occasions much loss of time; but so great is the simplicity of the machine that it still continues to be favourably regarded by the turners of such simple articles as the legs of chairs, tables, balusters, &c., in soft wood. It is also used in Spitalfields by the bobbinturners, who work in alder, &c.

The watchmaker's lathe, commonly called a turn-bench, or a turns, is a small copy of the pole-lathe, but it is very delicate in its construction, and is made entirely of metal. When the work is very small in diameter, as is often the case with the spindles or arbors, as they are technically termed by watch and clock makers, the cones, or male centres,' cannot be used. Hollow or female centres are substituted for them, and the extremities of the work are pointed instead, and rest in the countersinks, or female centres. When the end of the work requires to be turned, it cannot be placed in the hollow centre, but is laid in a shallow groove formed in the circumference of the piece of round steel that forms one of the centres of the turns. If the height of the centre cannot be


THE PRINCIPLES AND PRACTICE OF PLAIN TURNING. 33

so regulated as to bring the work level, a flat or step must be filed in the centre, which i.S thus made half round for a little distance from the eri.d. The groove is then made in the flat, and the work lies partly imbedded therein ; about half its diameter, however, is above the le;,el of the flat, and can be operated upon by either a file or a· cutting tool. A small brass sheave or pulley is fixed on the work, and rotary motion is imparted by mea11s of a light bow, the string of which is coiled once round the pulley. The string is generally a piece of very fine gut, but sometimes a horsehair is used for delicate work. The operator moves the bow in a slanting direction, holding the lower end, which is next him, between the thumb and forefinger of the left hand. The tool, which is held in the right hand, is applied while the work revolves towards him, and is slightly raised during the reverse motion.

Although the general principles of the lathe may be said to exist in the pole-lathe and turns, yet many of the most important operations of turning could not be executed in them. The mandrel, or chuck-lathe, which consists of a horizontal spindle, that revolves with great truth in suitable bearings or supports, possesses not only all the capabilities of the pole-lathe as regards the external turning of work, but also enables us to hollow out or bore the object, if desired. This is effected by securing the work to the end of the mandrel, which, for this purpose, i:;

allowed to project a little way beyond the support. By this arrangement the right-hand centre, which is essential in the pole-lathe and turns, may temporarily be dispensed with, and the face of the work be left clear for the tools.

A suitable pulley is permanently fixed to the mandrel, and occupies the space between the bearings. Rotary motion is imparted to the mandrel in different ways, according to the size of the lathe and the power required to be transmitted. The foot-lathe, which is employed for turning small and light works, is driven by the operator pressing his foot upon a treadle, which is in communication, by means of a short rod, with a cranked axle, carrying a grooved wheel considerably larger than the pulley on the mandrel. The motion transmitted from the treadle to this grooved (fly) wheel is communicated to the pulley by a line or gut; the action is precisely similar to the knifegrinder's wheel, which may frequently be seen in the streets.

When more pow.er is required than can be derived from the treadle, a large hand-wheel, several feet in diameter, is situated at some little distance behind the lathe. A boy is generally hired to turn this wheel, which he does by means of a winch-handle. An endless line, crossed like the figure 8, effects the communication bet·ween the driving-wheel

D



and the mandrel pulley. Large and heavy works demand more power than can be obtainecl from the hand-wheel; consequently, horse, water, or steam power is employed, according to circumstances. The lathe is then called a power-lathe.

The wood-turner's lathe is generally made of hard wood, and is of very simple construction. The support for the mandrel is fitted with metal bearings, in which the latter revolves with very little friction. As long works require to be supported at both ends, a movable block, :fitted with a centre in the manner of the pole-lathe, is added. The bench, or bed, as it is technically called, upon which the supports are fixed, is also made of wood, which answers the purpose sufficiently well ; it would, however, be unsuitable for a lathe intended for metal turning.

Having thus briefly noticed the general principles of the lathe, we will now consider the form of this useful tool best adapted to the requirements of an amateur who may be desirous of taking his first lessons in the art of turning. _ Fig.' 1 represents the front elevation of a mandrel foot-lathe adapted for general light hand turning in both wood and metal. With the exception of the foot-board, T, of the treadle, the lathe should. be constmcted entirely of metal.

A A, the bed, which is a strong cast-iron frame, in construction somewhat like a long narrow box turned bottom upwards. The bottom, or, as it becomes in this case, the top or face of the bed, is planed very true and smooth in a planing-machine. In the centre of the bed, and ex_tending throughout its length, is a gap, the u8e of which we shall consider presently.

B, is the headstock, or support for the mandrel, M, upon which latter is secured the speed pulley, or grooved rigger, 0.

D, is the movable support for the back centre, and is distinguished froin the headstock by the name, sliding poppet head.

E, the ordinary form of hand-rest; it can be fixed in any required position between the headstock and sliding poppet head, and can be raised or lowered to suit the turner's convenience.

S S, are two cast-iron frames, or standards, in the form of the letter A, to which the bed of the lathe is strongly bolted. R R, is the crank axle upon which the grooved speed or fly-wheel, F, is fixed. The axle is made of wrought iron, and is mounted on steel centres, P P, which answer exceedingly well, if properly proportioned to the weight they have to carry, and there is very little friction attending their use. The

, centres are fixed in cross bars, forming part of the A frames. When the weight on the crank axle is considerable, the centres are apt to wear


'l'HE PRINCIPLES AND PRACTICE OF PLAIN TURNIXG. 37

unsatisfactorily, and may increase the labour of treading very materially. \Vhen <t very heavy fly-wheel is employed, or when it is necessary to have two wheels, one at each end of the axle, the extremities of the latter should be placed on friction rollers, which will reduce the friction to a minimum. vVe may perhaps haye occasion to speak of this contrivance hereafter.

H H, the axis of the treadle, which, like the crank axle, is mountecl on centres, one at each end.. The foot-board, T, is attached to the axis by three iron bars, springing at right angles from the latter; one near each encl of the board, and one in the middle. The treadle and crank itre frequently connected by a short rod, having a hook formed at each extremity ; the lower encl of the rod engages a small loop or eye in the centre bar of the treadle, while the upper encl actuates the crank. Considerable friction attends this arrangement, and it is very inferior to the endless chain and friction pulley.

I, is an en~less chain formed of numerous flat plates, .which are punched out of sheet iron. Each link of the chain consists of several plates ranged side by side. The ends of the plates of every alternate link are placed between the plates of its neighbours i~ the length way, m, in this case, circumference of the chain. Owing to this, half the links a.re composed of an even, and half of an uneven number of plates. The ends of the plates of the neighbouring links are connected by a pin, which passes through them all, and is then riveted over the two outside plates, to make all secure. The number of plates required to make a link is regulated by the strain to which the chain will be subjected, and also by the limited space the chain must occupy.

The crank pin should be a little longe~ than the width of the chain, to allow the latter to work freely over it. The chain is placed in communication with the treadle by means of the frictiOn roller, W, which is a cast-iron wheel or pulley, about four inches in diameter. An eye · or loop is formed in the centre har of the treadle frame for the reception of the roller, and an iron pin passes through the sides of the loop fol.· its axis. The roller hai> a flanger on each side, to keep the chain in place and prevent it from grinding against the sides of the loop.

The line, g, is generally catgut; the ends of which are attached by a steel hook and eye. The hook and eye are formed with sockets, into which the extremities of the gut are screwed. When selecting them, care must be taken to get the correct size, for, if the sockets be too small, the gut will not screw in properly; and if too large, the screw can have but a,n imperfect hold.· If you have a screw-tap that :fits the sockets, or cut a bit of soft wood to the right size, and screw it in, you obtain at


38 THE LATHE, A.ND HOW TO USE IT j OR,

once an exact pattern or gauge for the correct size of gut. Before attempting to screw in the gut, the extreme ends must be slightly pared to make them taper, and a little oil should be applied.

We must caution our readers against making the line too tight, or, in other words, too short. If this is done, an unnecessary and injurious strain will be thrown on the mandrel bearing, and the hook and eye are very apt to be torn off, especially if the gut shrink, owing to a sudden change of weather.

Some people prefer gutta percha to catgut for lathe-bands. The ends of a gutta percha band can easily be united by gentle heat; the ends should be cut at an angle, in order to make the surface of the joint as large as possible, and then applied to a piece of flat iron that has been made sufficiently hot just to melt the gutta percha without injuring it by burning.

Both ends should be melted simultaneously, pressed together, and then left to cool. This material is liable to break at the join~, and the band unavoidably becomes shorter every time it is reunited. We strongly recommend our readers to give preference to the gut line, which, although much more expensive, will work better, and outlast many gutta percha bands.

An enlarged side view of the headstock, partly in section, is given in fig. 2, and an end elevation in fig. 3.

B B, is the base, which must be planed quite true, in order that the head may rest firmly on the · surface of the bed. A strip, E E, solid with the head, fits between the inner edges of the gap which extends throughout the length of the bed, A A, shown in section in fig. 3. It is necessary that the centre of the mandrel, M' M, S, should be exactly parallel to the centre of the bed in the direction of its length. As it is somewhat difficult to insure absolute truth in this particular, the strip, E, is often :made a little narrower than the gap to allow of adjustment, which is sometimes effected by thin wedges inserted at two cross corners.

The headstock is secured in its proper position by the two bolts, I I~ which screw into the solid metal forming the bottom. The lower ends of the bolts (also'screwed) l)ass through clearing-holes in a plate or rib, that is cast solid with the bed; a washer-plate is slipped over the end of each bolt, two nuts are then added, and screwed up tightly.

H H, form the supports for the mandrel, M' M, the front end of which revolves in a collar, or bush, while the back end turns upon a cone centre, c. The part, C, of the mandrel is enlarged, and made slightly conical, in order that any :;lackness occasioned 1Jy wear may be



obviated by the larger end of the cone working towards the small end of the bush, b'. This bush is straight or parallel on the outside, and is· formed with a flange or rim, b', which beds against the face of the headstock, H', and prevents the bush from passing through the hole in which it fits.

Mandrel bushes are sometimes made of steel; but this material is very apt to crack in the hardening process, thus spoiling work upon which much time and care have been bestowed. Case-hardened iron is, therefore, frequently employed in preference to steel, when the bush is large,· but it does not wear quite so satisfactorily. As we shall have occasion hereafter to speak concerning the processes of hardening an<l tempering, we need not enlarge at present.

After boring the bush within, and turning it outside to the proper diameter, to fit tightly in the hole that has been bored in the head, H', it must be hardened. The cone, 0, on the mandrel, having been turned to fit the bush, it must also be hardened, and then ground in the bush with emery and oil. When the interior of the bush and the mandrel cone fit fairly, the bush should be driven into its hole in the headstock, where the grinding process must be completed, the back centre, R, c, of w11ich we must now speak, being in its place.

The centre of the hole occupied by the screw centre, R, must be precisely in a line with that of the mandrel bush ; otherwise, the lathe cannot work properly, and if the inaccuracy exceed a very trifling amount,

. the hole must be plugged up and rebored. The screw, R, should just fit the hole, but must pass through it without requiring to be driven by a hammer. The lock-nuts, n n, when screwed up to thefr respective facings, which must be truly square to the centre of the hole, effectually fix the centre in the requfred position.

A small hole, filay_ a quarter of an inch in diameter, must be drilled about an inch up from the end, M', for the double purpose of clearing away the metal in front of the extreme point of the centre, and forming a receptacle for oil, which is introduced at the hole O' ; this latter hole is temporarily closed with a screw-plug. The conical point must then be hardened, and likewise the end, M', of the mandrel, in which the hollow or counterpart cone is made.

An oil-hole, O, must also be made through the top of the head, for lubricating the front end of the mandrel.

The screw, S, on the nose of the mandrel, should have a strong, coarse-pitched thread, to enable it to withstand the wear of constantly changing the chucks, and the strain when turning hard materials. The diameter of this screw must be somewhat less than that of the small end


40 THE LATHE, AND HOW TO USE IT.

of the cone, C, in order to form a sufficient shoulder or collar, j, for tl1e chuck8 to bed against when screwed home, otherwise they will be apt to get out of truth.

When it is necessary to remove the mandrel, the back centre, R, must be withdrawn ; the mandrel can then be slipped back until the cone, C, is clear of the bush, b. The nose, S, being smaller than the internal diameter of the bush, we are enabled to raise the end, M', and remove the mandrel obliquely.

The necessity for the greatest truth and perfection of workmanship will be admitted when it is understood that the mandrel must revolv~ easily and smoothly, not harder at some points than at others, and yet be entirely free from slackness. The back centre must be set forward until the cone, 0, beds fairly in the bush ; the lock-nuts may then be slightly tightened. If it is found that the mandrel has been jammed fast, the inside nut must be unscrewed a trifle, and the back one tightened, to draw the centre back. A smart, but not heavy, blow must be administered with a mallet to the encl of the nose of the mandrel, and if it then revolves freely and equably, we must try whether there is any end shake. This is easily ascertained by standing behind,the back centre, holding the pulley in both hands, and endeavouring to move it backward and forward in the direction of its length. If no motion is perceptible, both the lock-nuts must be equally tightened.

We will now turn our attention to the sliding "poppet-head," shown partly in section in fig. 4 ; fig. 5 is an encl elevation· of the same. The " supports," P P, and the strip, EE, are similar to the headstock, figs. 2 .and 3, and of like material. The supports carry, and are solid with, a cylindrical body or barrel, B B (shown in section), within which slides a wrought-iron cylinder, H H'. The steel cent.re, C, is formed with a conical neck or stem, d, which fits the interior of the cylinder at the encl H'. The other end, H, is bored smaller, and is screwed to act as a nut to the long screw, S S', by which the cylinder is moved in or out, as required. Excepting the part forming the nut, the interior of the wrought-iron cylinder is bored sufficiently large to clear the screw. The screw is turned round in either direction by the hand-wheel, W, which, for convenience, is fitted with a handle, L,-although it is frequently worked by taking hold of its circumference.

(To be continiwd.)


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r To /aoo Page 96, THE LATHE,


96

THE LATHE, AND HOW TO USE IT ; OR,

THE PRINCIPLES AND PRACTICE OF PLAIN TURNING.

B Y TE M PL E T H 0 R 0 L D.

CHAPTER I. (continued).-THE LATHE.

Sit is essential that the screw should only rotate, and not move in the direction of its length, a collar, f, is formed near the back end, and bears against a steel plate, l l, which is secured with small screws to the head. The thread of the screw, S S, terminates at the collar, but a plain cylindrical stem is continued behind

the collar, and to this the handwheel, W, is secured. The front face of the wheel-boss bearing against the outer face of the plate, l l, and the collar, f, resting on the inner face, effectually prevents any movement of the screw in an end-long direction. From this it is easy to understand that by turning the screw round in either direction, we can cause the cylinder, H H, to move in or out, as may be desired.

As the cylinder, H H, would be apt to turn round with the screw, and thus neutralize the action' of the latter, a narrow groove, or key-way, is made along one side of the cylinder. A key is fixed inside the barrel, BB, near the front end, and projects just sufficiently to engage the groove or key-way. Although the cylinder is made to fit the interior of the barrel, throughout its length, as closely and accurately as possible, yet it is necessary to provide a set-screw, T, to steady it when projecting some distance from the head. A small saddle-piece, r, made of brass, is let into the upper part of the barrel, and is placed between the point of the screw and the cylinder, to sa"'fe the latter from being bruised.

The centre is shown separately in fig. 6. The shank, D, is slightly conical or taper, and must exactly fit the hole at the extremity of the cylinder, H H, as any slackness would throw the work out of truth if turned between centres. The shoulder of the straight part at the base of the shank must not rest against the end of the cylinder, H H, and a


THE LATHE, AND HOW TO USE IT. 97

-clearance of at least I-16th of a~ inch should be allowed between. them to en.able the shank to find its proper bearings in the hole. The shaD.k is not subjected to much wear, nevertheless the pressure upon it is sometimes sufficient to cause it to sink a little deeper in the socket. If the taper is very slight the shank will jam itself tight in the socket, and as it would disfigure the straight part, or collar, if we endeavoured to remove the centre by force, the small end of the shank should be su:ffi" ciently long to come in contact with the extremity of the screw, when the cylinder, H, is drawn nearly home (as seen in fig. 5); the centre will thus be expelled easily, and without injury. -If the centre is required for heavy metal turning, it should be large, as shown by the dotted lines; but for general light work it is more convenient_ when reduced, as represented in the figure.

The centres themselves upon which the work revolves must not be very acute, or the points will be apt to break off when turning hard material, and if too obtuse the work will be liable to. fly out of the centres, as they cannot penetrate sufficiently to afford secure support. An angle of about thirty degrees will be found satisfactory for ordinary work. When the character of the work is variable, that is, sometimes heavy or rough and occasionally light and delicate, it will be advisable to be provided with two or three pairs of centres. The pair for light work may with advantage be more acute, say an angle of about twenty-five degrees.

It must be borne in mind that when turning work between centres it is often necessary to change it end for end ; therefore it is important that the pair of centres in use be as nearly alike as possible, otherwise the work will be liable to run untrue when reversed. The centres are made of steel, and that in the sliding head is hardened to prevent too rapid wear. As the centre in the mandre} revolves with the work, it is much less subject to attrition, and need only be slightly hardened.

The ordinary form of hand-rest is seen in fig. 7 ; R is a cast-iron plate, or saddle, made true on the under side that it may lie fairly on the surface of the lathe-bed, BB. The front end of this saddle is furnished with a boss or socket, G, cast in a piece with it, in which the stem, S, of the rest, EE, fits. By this arrangement the rest can be raised, lowered, .or placed at any angle to suit the convenience of the operator. A set screw, P, is provided, to secure the rest in any required position ; when slackened, the stem, S, is at liberty, but when tightened, the stem is forcibly pressed against the opposite side of the hole in the. socket and held fast. The rest, E E S, is made of wrought iron, and owing to its having some resemblance to the letter T, it is called the T rest ; it is mostly employed for wood turning.

H


98 THE LATHE, AND HOW TO USE IT ; OR1

A cros( section of the saddle, R, is exhibited in fig. 8, which also shows the arrangement for holding down. The holding-down bolt, T, screws into a wrought-iron nut, N, formed with a dovetailedhead which fits into, and is capable of sliding in, a similarly shaped groove or recess extending throughout the length of the saddle. The plate, W, also of wr.ought iron, bears against the under side of the lathe-bed, and serves as a strong washer for the shoulder of the handle, L, to press upon when the .bolt is screwed up to fix the saddle. When the bolt, T, is slack,

. the saddle is at liberty, and can be moved along the bed, drawn out or pushed in at right angles to the latter, or can be set slightly at an angle either to the right or left, as may be required.

CHAPTER N.

CHUCKS, ETC.

WE must open this chapter by making an apology. Our readers would perhaps like, now that the lathe has been introduced to

their notice, td begin their lessons in turning at once. As this, however, fa quite out of the question, we must beg to be excused on the plea that there is no "Royal road to learning" turning, or anything else that requires preliminary grounding and investigation. This being our view of the matter, we shall explain some of the apparatus, tools, &c., required in turning plain objects, before asking our readers t_o take even their first lesson in the turner's craft.

By referring to fig. 2 it will be seen that the nose of the mandrel is screwed, in order that the various cliucks required in turning may be secured thereto, removed, and changed at pleasure. Any piece of wood or metal screwed upon the nose of the mandrel for the purpose of holding work or tools is called a "chuck," and very numerous are they, and much ingenuity is displayed in the construction of many of the more complex among them.

The centre-chuck, figs. 9 and 10, is the first, and one of the simplest of the group absolutely necessary for even the plainest work. The body, or." chuck," B' B, may be either of cast or wrought iron; if the former, increased thickness or diameter must be allowed to secure strength equal to the latter material, which is decidedly preferable for this and similar small chucks. The socket, B', which screws upon the nose of the mandrel, is made a little larger than the part in which the cone, d, of the



centre, O, fits. The centre must :fit the chuck accurately and tightly, otherwise it will throw the work out of truth, and occasion much trouble. It is sometimes screwed into the chuck, which is quite as satisfactory and certainly much better than a shaky cone, and it can as easily be replaced by a new one. The driver, D' D, is made of steel, and is square in section, as may be seen in the perspective view of the chuck, fig. 10. It is capable of sliding in or out, so that the arm, D', which is the means of imparting the !fiOtion of the mandrel to the work, may be brought in contact with the carrier, which often varies in size with the work.

A set screw, S, penetrates the side of the chuck to secure the driver in any required position.

Another form of driving-chuck often used is represented in fig. 11. The circular plate, P, is generally from four to six inches in diameter, but this of course is regulated by the size of the lathe, and the height of the centre from the top or face of the bed. The centre may be fixed in the plate itself, or can be formed with a taper stem or shank to fit a conical hole made up the mandrel in a similar manner to the cylinder, H' H, in the sliding poppet head, fig. 4 ; if the latter . plan is adopted, the nose of the mandrel must be larger in diameter than otherwise would be necessary. The driver, D, is formed with a shank having a square to fit the slot, S, and is thus prevented from turning round when we screw up the nut by which the driver is fixed. The length of the square part of the shank is a little less than the thickness of the plate, P ; the remainder of the shank is round, and is screwed for the nut, which, being situated behind the plate, cannot be seen in the figure. Two slots in a line, one on each side of the centre, and two drivers sometimes are employed in order to relieve the centre of the strain which is brought upon it when one driver only is used. A boss, or socket, is formed on the back of the plate into which the nose of ·the mandrel screws; this can-

~ not, however, be seen in the figure. It may here be well to observe that the size of a lathe is in general

regulated by the height of the centres from the face of the bed, and by the length of the latter. The height of the centres limits the diameter of the work, which cannot exceed twice that distance, unless a special provision be made in the bed. This provision consists simply in a U -shaped cavity, called a well, or break, which is situated immediately in front of the bead stock, and enables us to employ chucks of much larger diameter than the height of the centres would otherwise permit. It will be understood that if the diameter of the work fixed on the clrnck be sufficient to dip into the "well," it cannot project far from the

H 2


100 THE LATHE, .A.ND HOW TO USE IT j OR,

face of the chuck without coming in contact with the right-hand side, or wall of the well, which thus limits the depth or thickness of the object to be turned. The diameter of work turned between the centres is, of course, always limited by the height of the latter; it is, therefore, sometimes necessary temporarily to raise the headstock and sliding poppet head by placing under them suitable metal " packing pieces."

The strut-chuck, which set'ves as centre and driver in one, is employed when turning wood between centres. Fig. 12 is a section taken in the direction of the length; fig. 13, an elevation; and fig. 14 is an end view, showing the centre point and knife edges. This chuck must be made of wrought iron or steel ; the knife edges, e e, and the centre, C, may be of the latter material, which, in forging, can be welded to a wrought-iron body or socket. The centre, C, as usual, supports only, and determines the position of the work, but the knife edges, e e, stick into it, and insure its rotation.

A perspective view of one kind of facing-chuck is shown in fig. 15. This chuck is often used for holding pieces of wood that are not circular, .and too short conveniently to be supported between the centres. The plate is of metal, quite fiat, and provided in the centre with a coarse, threaded screw, S, upon which the work is fixed. This screw must be only slightly taper, otherwise the work will speedily become slack. If the screw hole be detrimental and cannot be plugged up after the work is removed from the chuck, some other method of holding the object must be adopted. In general, this chuck is only used for rough or preparatory work, and for holding a piece of hard wood, which is to be hollowed out to serve as a cup-chuck. Sometimes we may require to face a piece of wood on both sides or ends, and it will be found that if the screw, S, is too taper or conical, it will not hold, if the work be reIDoved and again :fixed with the same side next the chuck. If the circumference of the work is to be turned, much greater steadiness will be secured by fixing the poppet head as close as convenient, and using the centre in the ordinary way. Unless we wish to hollow out, or bore the work, the presence of the back centre (as it is often called) will generally not interfere with the free use of the tools as applied for simply facing the end of the work.

Figs. 16 and 17 represent another variety of the facing-chuck. The central screw is omitted, and fine short steel points or spikes are fixed in the face of the plate. This chuck is used when a hole in the centre of the work would be detrimental. Even the small holes made by the spikes would be injurious when the face of the work is required to be quite smooth. Sometimes a piece of wood a little thicker than the


THE PRINCIPLES AND PRACTICE OF PLAIN TURNING, 101

ength of the spikes, is pressed home, tapped lightly with a small mallet in the neighbourhood of the spikes, to insure its lying "dead" upon the plate, and then faced flat to receive the work. If the work be much smaller in diameter than the wood fixed on the plate, it will be unnecessary to face more than sufficient to receive the work, which must be glued thereto, and then left until the cement has become quite hard. The work may be supported and keep in close contact with the wood while the glue is drying, by fixing the sliding poppet head in a convenient position, and then, having removed the back centre, bringing the end of the cylinder, H' (fig. 4), against the work by turning the-handle wheel. A smart blow will disengage the work from the wood to which it was glued, and the opposite side can, if necessary, be glued to the. chuck. If the surfaces to be glued are large, it is advisable to place a pie0e of thin paper, the full size of the work, between the latter and the chuck, to facilitate their separation.

The cement-cliuclc, which is a plain flat plate, having neither screw nor spikes, is sometimes used for holding thin pieces of bone, ivory, &c. The lathe is set rapidly in motion, and the cement, which is in the form of a i;,tick or lump, is held against the revolving plate. The heat occasioned by friction melts the cement,-a little of which adheres to tha plate. The ivory, or other small work, must quickly be pressed upon the plate, before the cement again becomes hard. Care must be taken to apply the cement very equally, and not in lumps, or thicker in some places than in others, otherwise it will be difficult to chuck the work truly.

We could give a receipt for making turner's cement, but as the· amateur will require very little of this composition, it is better to purchase it at the tool-shop.

The simplest form of hollow, or cup-cliuclc, is seen in section in fig. 18. It is generally made of boxwood, and is sometimes strengthened by a metal ring, r r, which is driven on tightly, to prevent the. chuck splitting when subjected to rough u:sage. The interior is bored. slightly taper, or larger at the mouth than at the bottom, so that the work, when driven in, is sure to be held firmly if it fits the mouth properly. Care must be taken not to allow the work too much taper on. the part to be inserted in the chuck, otherwise the latter is almost certain to be split or distorted, besides considerably increasing the difficulty of extracting the work, which is very likely to be injured or broken . during its removal. It should be borne in mind that very little taper, and a very moderate degree of tightness, are amply sufficient to hold the_ work if the tools be properly applied.


102 THE LATHE, AND HOW TO USE IT ; OR,

Unless the wood is very thoroughly seasoned, it is apt to cast, and the collar; c, of .the socket will not always screw up fairly to the shoulder of the mandrel (/, :fig. 2), thus throwing the chuck out of truth. The only remedy is to pare away the face of the collar where it bears hardest on the shoulder until it again rest in contact all round. Of course the body of the chuck can no longer run true, and we must rebore it before it can be used. As a change in the weather may distort it.the next day, and perhaps make it worse than before, we must find some more certain means of effecting a cure.

Instead of forming the socket of wood or in a piece with the body, it should be made separately of metal, and provided with a circular flange or plate, at least two inches in diameter, by which it must be secured with carpenters' screws to the wood intended for the chuck. This plan possesses great advantages, and the threads or screw in the metal socket will outlast many wooden ones, the threads of which are very liable to "strip," or break off long before the body of the chuck is worn out. If we are furnished with three or four metal sockets, we can fix them to pieces of wood of any size convenient for our work, and can in a few minutes with very little trouble remove a socket from a worn-out block, and secure it to a new one. ·

Fig. 19 is a sectional view of a spring-chuclc, which is often used for holding very slight work. It is sometimes made of wood, but metal is much to be preferred, not only on account of the greater neatness · which may be secured by its use, but also because the latter material does not warp and twist as wood frequently does, on change of weather. The body of the chuck, B, B, is much thinner than in an ordinary cupchuck (fig. 18), and is turned taper or conical on the outside, the base or largest end being at the mouth. About six small holes, only three -of which, h h h, can be seen, are drilled at equal distances from each other on the circumference ; and near the bottom of the " cup " or body of the chuck, narrow slits or saw kerfs, ch, ch, ch, are cut from the mouth to join the holes, as shown in the figure. · When the work is pressed into the chuck, the latter slightly expands owing to the elasticity derived from the several longitudinal divisions or kerfs, which practically convert the cup into so many flexible fingers that grasp the object with a greater or less degree of tightness, according to the amount of their dist.ension. A strong movable ring, R R, is fitted to the_ body, partly to prevent its being distorted by any attempt to force in work too large for its capacity, and also to assist in holding the object by compressing the cup more closely round it, by drawing the ring forwarcl towards the mouth. It will be understood that the ring being in ca-


THE PRINCIPLES A.ND PRACTICE OF PLAI:N TURNING. 103

pable of expansion, must powerfully compress the cup as it is drawn toward the large end, which yields and clasps the work that has been, inserted.

If our readers wish to make a cheap spring-chuck, the back and socket, S S, can be m.ade of well-seasoned boxwood, and the body, B B, may be constructed from a piece of thick brass tube, into which the former must be tightly driven. The tube should be further secured by six (or more) small screws, t t; inserted at regular distances. The tube must be turned conical on the outside as in fig. 19, and also slightly taper inside, largest at the mouth, before the holes, h, h, h, and the kerfs, c, c, c, are made.

Cup-chucks made of lead are often used by turners of light kinds of brass work. A_ piece of wood must first be turned to the proper external shape and size of the intended lead chuck, to serve as a pattern with which the impression can be made in suitable sand, which, on withdrawing the pattern or model, will form a cavity, called a mould, to receive the liquid metal.

As lead would be much too soft for the socket to screw on the man(lrel, one made of brass must be placed in the cavity left in the mould by that part of the pattern which represents the socket. The end of this brass socket, which is to be united to the body of the chuck, should be formed with a tolerably large square flange with sloping or dovetail sides; in orde~ that the meta.] may run round them, and hold the socket fast. If the face of the socket flange is filed bright, and covered with a thin coat of either tin or so~ solder, the lead will hold the brass much firmer. A_ little block tin melted with the lead will make it harder and improve the chuck.

Small chucks of about three or four inches diameter are cast solid. With a view to economy, the newly-cast chucks are first employed for small work, and are bored larger and larger until they become too thin, when they are melted and recast.

There is very little, if any, elasticity in lead, and being soft it is easily put out of truth by extracting the work ; it is, therefore, generally necessary to bore it afresh every time it is used. Some people who are too lazy to recast their chucks, or neglect to provide a sufficient number for their work, employ what they facetiously call the "thickening tool." If they cannot find amongst their stock a chuck small enough to admit of reboring, the hammer will be freely applied to the face and circumference of the one nearest to the required size until the lead by yielding has reduced the internal diameter sufficiently to bear reboring. This practice, to say the least of it, is slovenly and



very unworkmanlike, and should never be adopted by those who pride themselves upon the neatness and good qimlity of their tools.

Fig. 20 is a perspective view of another variety of cup-chuck, made of cast iron, and employed for holding short pieces of round brass or iron that we cannot advantageously place between the centres. Three strong steel screws, S, S, ~S, are screwed tl1rough the body of the chuck at equal distances apart. The work is held between the points of the three screws, which can be so adjusted as to bring it exactly into the centre. Large chucks of this description are generally fitted with a second row of screws, a little behind and midway between the foremost set, in order to afford additional support to the work. Six screws, three in each row, are quite sufficient, although eight screws are advoc11,ted by some people. The screws are formed with capstan heads, through the sides of which holes are drilled, to admit the tapering point of a simple instrument, fig. 25, called a tommy. The diameter of the holes must not exceed one-third the thickness of the head, and when the latter is small, one hole straight through is as much as it will bear. When the head is large, a second hole is made at right angles to the first.

A useful kind of chuck for holding drills and short pieces of round'. metal is shown in fig. 21. The shank of the drill must fit the hole in the chuck closely, and a slight fl.at should be filed on one side to enable the point of the screw, R, to obtain a fair hold. Of course the round metal we may wish to turn must fill the chuck, otherwise it will run out of truth when the screw, R, is tightened. Small drills are often required in the course 01 our work, and as the shanks are made in proportion to the cutting parts, it will be found very convenient to have two or three small socket chucks formed with shanks, S, fig. 22, to fit into the larger chuck, fig. 21. The large chuck might conveniently have a hole or socket of about five-eighth inch diameter, and the smaller chucks, say three-eighths and a quarter of an inch respectively.

The larger chuck, :fig. 21, may be made of cast iron, but the small ones should be either of wrought iron or gun-metal. The screws must be of steel, and about two of the last threads at the ends should be turned off, and the tips hardened to prevent them from spreading out or becoming burred by the pressure to which they are subjected. This precaution should always be adopted for cup-chucks, and all set or pinching screws in whatever situation they may be employed, otherwise it will be difficult, after a little service, to remove the screws, as the ends, by spreading, ~ill have become larger than the holes.

The arbor-chuck, fig. 23, is generally made of gun-metal. It is used for holding small annular work, such as rings, &c., thus saving the



trouble of turning a new arbor, or mandrel, as it is often called, for each variation of size in the work. The arbor must not be formed with much taper, or the work will slip off when the tool is applied to the left-hand side~ or towards the socket, S. The socket may be dispensed with, and a shank, as in fig. 22, can be made to fit the drill-chuck, fig. 21, but the liability of getting out of truth is greater in the latter arrangement.

Fig. 24 is a spanner made of wrought iron, used for screwing up and removing the chucks that have no projecting parts by which they can be held. Those chucks for which the spanner is to be employed are provided with a hexagonal or six-sided collar to fit the jaws, J J. The centre-chucks, figs. 9, 10, and 11, can be screwed upon and unscrewed from the mandrel by the carrier, D D, and the screws of the cup-chuck, fig. 20, will answer a similar purpose.

Of the tommy, fig. 25, we have already spoken. It must be made of round steel drawn down or made gradually tapering from the bend to the points, which should not be too sharp. One end, as may be seen, is bent at a slight angle to the longer arm, thus enabling us to use it in corners where the straight arm could not be employed.

(To be continued.)


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161

THE L.A.THE, AND HOW TO USE IT ; OR,

THE PRINCIPLES AND PRACTICE OF PLAIN TURNING. ' .

BY TEMPLE TH 0 R 0 L D.

CHAPTER II. (continued).-CHUCKS, ETC.

HE face-plate, figs. 26 and 27, is usually employed for holding square, rectangular, or hTegularly shaped work which obviously cannot be fixed in a cup-chuc~. It is generally as large in diameter as the height of the centres will permit, to afford ample space on its surface for the work, and the means of securing the

latter. Cast iron is the material commonly employed for face-plates, and, indeed, for most of the ordinary chucks, if :they exceed five or six inches diameter, as brass would be too costly, and at the same time less suitable, for a lathe intended for ordinary plain work.

The face, or front side of the plate against which .the work is placed, must be very carefully turned, and made quite flat ; and its truth in this particular should be tested by a correct steel straight edge, applied across the centre. The edge or rim also must be turned, but the back may remam in the rough, and can be painted, as the hard skin or scale formed in casting increases in some degree the stiffness of the plate, It will be seen, by reference to fig. 26, that the plate is perforated with several slots, or rectangular holes, through which are passed the screw bolts for securing the work. The thickness must be increased, to compensate for the absence of the metal in so many places, otherwise the plate will .be distorted, or drawn out of truth, by the unequal strain to which it unavoidably is often subjected by the bolts employed to bind · the work to its face. As the bolts can seldom act immediately upimthe · work by passing through it, rectangular wrought iron plates are used in the manner of clamps. Aslot large enough to allow the bolts fo pass through easily, occupies the centre of each pliJ.te, and extends .to . within a short distance of the ends. One end of each plate rests upon the

){



work, and the other extremity is supported by a bit of hard wood, or a piece of metal, in order that it may be level. The number of plates to be used depends upon the magnitude and character of the work ; two or three are in general sufficient, and we can seldom apply more than four advantageously. The bolts should be formed with square necks immediately under the heads, to fit the slots in the face-plate, to prevent them from turning round when the nuts are being screwed up. This simple device saves much trouble, and the left hand is at liberty to support the work, if necessary, until the bolts take hold, instead of being engaged with a second spanner to keep the bolt neads steady while the nuts are being tightened.

It not unfrequcntly happens that we require to face the work throughout, and as the ends of the plates would prevent this, another method of holding it must be adopted. Four contrivances called dogs, each armed with a steel set-screw, which takes effect on the margin of the work, are secured to the face-plate . . The dog is very simple in construction, consisting substantially of a

rectangular piece of wrought iron somewhat wider and thicker than the width of the slots in the face-plate, as it must not pass through them. It is provided at one end with a screw shank with a square neck about the same size as the ordinary bolts used with the plates. The length or height of the dog above the surface of the face-plate need not be greater than the head of the set-screw renders necessary. This screw is "tapped " or screwed through the widest side of the dog, · and must be parallel to the surfac~ of the face-plate, or, what is the same, at right angles to the shank by which the dog is secured in its place.

The dogs are fixed opposite one another, one in each of the four longest slots of the face-plate. They can be placed at any distance from the centre, within the length of the slots, that the shape of the work may render desirable. The closer the dogs can be fixed to the l'.Dargin of the work .the better, as the" set-screws act ·with greater effect when their points do not project far from the dogs.

It may be observed that separate dogs, plates, &c., are usually only employed for securing metal works to the face-plate, as wood can be glued to a temporary wood facing attached to the face-plate with ordinary carpenter's screws, or in the manner already described under fig. 16.

The aog-chuc'k proper, figs. 28 and 29, is one of the most useful of the chucks employed by the plain metal turner. Fig. 28 is a perspective view, showing the front of the chuck and the four dogs, D, D, D, D. The plate itself is made of cast iron, and is about the same size as .the



face-plate, and, like it, must be very carefully turned. Only four slots, one for each dog, are made through the chuck. The dogs, as may be seen in the engraving, are much wider than the slots, and they are formed with square blocks, which accurately fit their respective slots; the .latter being made quite trne and parallel inside to afford, as much steadiness as possible to the dogs. A screw stem or short bolt is formed solid with the square block on each dog, and when the latter is put in its place a small iron plate about a quarter of an inch thick, having a hole in the centre a trifle larger than the screw stem, is slipped over the latter; a nut is then placed on the stem and screyed down to the plate, thus :fixing the dog.

As all this takes place behind the chuck, it will be better understood by referr~ng to the back view, fig. 29. The nuts for fixing the dogs are seen at n, n, n, n, and the plates against which they are screwed at P, P, P, P. A raised strip or facing is made on each side of the slots for the plates to bear upon. One of each pair is represented at F, F, F, F; they must be very carefully wrought, and must

1

be quite parallel to the front of the chuck, otherwise the dogs will be slack in some positions and stick fast in others. The dogs are moved up and down within the range of the slots by four strong screws, C, C, 0, C, one to each dog. These screws are so :fitted as to be incapable of moving in the direction of their length, and can only be turned round, either to the right or left as may be required, to move the dogs towards or from the centre of the chuck. The ends of the screws, K, K, K, K, fig. 28, are formed with squares, and the socket, K, of a suitable key or spanner, fig. 30, is slipped over them, by which means we obtain the necessary leverage, and can alter the position of any of the dogs separately at pleasure.

The outer circumference of the dogs, R, R, R, R, is intended for carrying annular or hollow cylindrical work, which is slipped over them; they are then drawn from the centre by means of their respective screws until they bear with the requisite pressure against the inner circumference of the work. The inner circumferences of the dogs give two sizes, the larger at I, I, I, I, and the smaller at B, B, B, B ; these are for holding work externally. It will be seen that the outer and inner circumferences of the dogs are roughened· or chequered to enable them to grip the work firmly.

Even when the dogs are brought as close to the c~ntre of the chuck as their corners will permit, they cannot hold work that is sm·aller in diameter than about the size of the .mandrel nose. This may be obviated by attaching to them with screws four temporary pieces or


THE PRI,NCIPLES AND PRACTICE OF PLAIN TURNING. 165

auxiliary dogs, for which · purpose two screwed holes, s, s, are made in each of the dogs proper, as may be seen in fig. 28. These pieces are about thick enough to fill the recess or step in the dogs, and make them level throughout. One end of each piece bears against the step, I, of the dogs, and the screws are thereby relieved of a great part of the strain that otherwise would be brought upon them when the dogs are in use. The holding-ends may be bored sufficiently small to hold work abo11t half-an-inch in diameter, if desired, but the cup-chuck, fig. 20, is generally preferred for this purpose. The auxiliary dogs are generally employed when the smaller circumference of the dogs proper is required to hold work that must not touch the face of the chuck, a space, perhaps, of half-an-inch being left between them to allow the tool to pass quite through the work without danger of injuring the chuck by cutting a groove or furrow in it. In this case the holding ends of the separate dogs are generally bored to the same size . as those of the dogs proper. The dogs are usually made of wrought iron case~harden~d,

which is tougher than hardened steel, and quite as serviceable in this position. Neither iron nor steel would long retain its shape at the holding points, if unhardened, and the checkering would soon be rendered useless.

When long and slender work is turned between the centres, an additional support must be provid·ed to impart the requisite steadiness. This support or bearing, shown in fig. 31, consists of a cast-iron frame, F, F, furnished with a block of hard work, W, W, through which is bored .a hole, B, the exact diameter of the work. The wood, seen separately in fig. 32, is held in position by the V or wedge-shaped formation of the inner sides of the frame F, which fit into corresponding grooves in the wood. After fitting the solid block of wood into the frame, the cap or plate, C, C, is placed above it, and . the nuts are: then screwed down.

The height of the frame must be such that the centre of the wood shall coincide with the centres of the lathe. The exact position of the centre for the hole may easily be found by fixing the frame temporarily in its place, and then securi~g the poppet head close to it, and screwing out the centre against the wood, which will be marked hy the point. A pair of dividers or compasses must be set to the radius, or half the diameter of the required hole, and with them a circle must be distinctly marked.

If the face of the wood on the side opposite to that on which we have made the circle be true, and at right angles to the lathe bed; the wood can be fixed on the face-plate, and the hole be very easily bored. The


166 THE LATHE, AND. HOW TO USE IT ; OR1

wood is adjusted on the plate by the circle, which must run exactly true< before attempting to make the hole. Before replacing the wood in the frame, it must be cut in half across the centre of the hole, and parallel to the bed of the lathe. The two halves can then be brought eloser together as the hole becomes too large by wear.

This bearing frame can be fixed in any required position between the heads, and must be- placed as close a·s possible to that part of the work which is being turned, in order to prevent it springing from the edge of the tool. The end of the work next the poppet head must be turned for a short distance to fit the hole in the bearing before the latter can be employed, and after :fixing it, the work must be reduced to the same diameter throughout its length, and the bearing must occasionally be moved towards the vicinity of the tool. The holding-down bolt, which· is similar to that of the poppet-head, passes through the hole, H, in the base of the frame, fig. 31, and is furnished with a washer-plate and nut~

The carrier, fig. 33, is a simple contrivance made of wrought iron, which is employed in conjunction with the driver, D, :figs. 9 and 11, for imparting the rotative motion of the mandrel to metal-work, when the latter is fixed between centres. The end of the work is placed within the bow or loop of the carrier, and the set-screw is then screwed down upon it. If the end of the work would be injured if bruised by the point of the set-screw, it must be protected by wrapping a piece of thin. sheet copper or tin round it before inserting it in the carrier. The stem or shank of the carrier must rest against the driver, which, as we have already shown,. is capable of being fixed closer to or further from the centre, to enable it to engage carriers of various sizes.

Fig. 34 represents the drilling-plate, which is very useful when wewish to employ [the lathe as a drilling machine. The stem, D, fits. into the end of the cylinder, H', of the poppet-head, fig. 4, and_ the ;work to be drilled is held against the plate, P, which must be quite flat. The drill, according to its size, is held in the drill-chuck, fig. 21 or 22. The poppet-head is fixed close to the drill, just allowing sufficient spacebetween its point and the face of the plate, P, to introduce the work. The lathe is set in:motion, and the hand-wheel, \V W, figs. 4 and 5, is turned round very slowly, great care being required to avoid too much prel3sure upon the drill. Great force can be exerted by means of ·the· hand-wheel screw, and many drills will be broken at first ; but a littlepractice will conquer all difficulties. \Ve shall notice drilling fully hereafter.

Sometimes, after fixing metal work in the chuck, it may be necessary



to lind the centre of the object before proceeding to use any of the tools, and even after the work has been partly wrought we may require to make or cut a deep centre to receive the point of a drill, &c. The centre can either be marked or cut with a graver, or diamond-pointed tool, but some practice is needed before even this apparently easy operation can successfully be accomplished. Little or no skill is demanded in the employment of the broach-centre, fig. 35, which can be used with the greatest ease and certainty. This centre is made like an ordinary cone-centre, and must be of the same angle : the stem, D, also must fit the end of the cylinder, H, fig. 4. Before hardening the cone, A B B, it must be marked out into four":''equal parts, and four :flats filed, leaving the lines of division standing as four sharp edges ; it 'must then be hardened and tempered like an ordinary cutting tool for metal.

"When about to use this centre, it must be placed in the cylinder of the poppet-head, which latter should be fixed as· close as convenient to th!l work on the chuck. The lathe is then set in motion, and the point of the centre is very gently pressed against the work by turning the hand-wheel slowly round until a centre of the required depth is made.

The boring-collar, or cone-plate, exhibited in figs. 36 and 37, is an important addition to the apparatus required in turnery operations. It consists of a cast-iron plate, PP, turned quite flat on both sides, and circular on the edge or circumference. Several conical holes, varying in size, are carefully bored through the plate, all the centres being equidistant from the centre of the pin, or axis, B, upon which the plate is capably of rotating. This pin, which is made either of iron or steel, fits a hole in the boss of the cast-iron support, or bracket, H H, shown partly in section in fig. 36. It will be observed that the pin is formed with a head at B, which prevents the plate slipping off, and draws it closely to the face of the bracket on screwing up the nut, N. A transverse section of the plate also is exhibited, in fig. 36, taken through the centre of the conical holes, C and D. The centres of the holes which are represented by the dotted circle in fig. 37 must correspond exactly with the lathe centres when, by turning the plate round, they are respectively brought into the highest position. The base or foot of the bracket, H H, is formed like that of the poppet-head, and a piece, EE, fits in the opening along the centre' of the bed, to assist in ·keeping it steady, and to insure its central position.

The boring-collar is used to support the end of cylindrical work when we require to bore it, as the back-centre cannot then be employed. If



the object is fixed either in the cup-chuck or the dog-chuck, and does not project much, ~t will probably be sufficiently steady to bear boring Without the assistance of the boring-collar. In the case of long work, however, or such as is supported only by the mandrel centre, either the boring-collar, or a bearing similar to fig. 31, is absolutely necessary.

The end of the work must be faced, and the circumference, or exterior, turned for a short distance trom, the extre~ity previously to placing it in the boring~collar, otherwise it will not only run untrue, but also injure the conical hole in which it revolves.

Everything being in readiness, the bracket, H H, figs. 36 and 37, is placed on the bed of the lathe, the large ends of the conical holes being towards the mandrel. The nut, N, is then slackened to allow the plate, P, to turn, if it he requisite to 'bring any particular hole opposite the end of the work. In selecting the hole, it is necessary to ascert~in, by trial, before securing the bracket, whether the work can pass through the small end, and if it does, a smaller cone must be tried. If the work enters the hole about an eighth of an inch at the large end, or is within the same distance of the most contracted part, it will be favourably situated, and indeed any position between these may be adopted.

As the centre . of the hole must correspond exactly with the lathe centres in all directions, not only as regards height, which is determined by the pin, B, and the bracket, H H, but also sideways-to ensure the latter, a mark, or line, must be made from the centre of each hole on the side of the plate next the bracket, and one lil;te must be drawn across the top of the boss of th,e bracket in the direction of its length. Supposing all these lines to be correctly placed, the centre of any ·one of the conical holes will tally with the centres of the lathe as the lines on the plate are brought in turn precisely opposite the line on the bracket : the nut, N, must then be screwed up tightly to fix the plate.

The bracket not having yet been secured, we can slide it along the bed towards the mantlrel until the end of the work takes its proper bearing in the conical hole which has been chosen for its reception. The work must be free to revolve easily, but without "end-shake." After screwing down the nut of the bolt that holds the bracket, we can shift

' the latter a trifle in either direction by striking it smartly on the foot with a hammer, if the work has been set fast, or has gained too much freedom by any movement of the bracket while securing it. The end of the work revolving in the conical hole must be kept' well lubricated with oil, otherwise the friction will cause the bearing surfaces to " cut," ·or wear into deep furrows, which will speedily ruin them.



Before bringing this chapter to a close we will notice a method of fixing rectangular work on the face-plate, when it is necessary to face it on two or more sides which must be square, or at right angles to one another. A perspective view of this arrangement is given in fig. 38. To the face-plate,. F, is bolted a castciron angle-plate, P D ; the nuts by which it iS secured are seen at b b. This angle-plate, or angle-chuck, is planed on the two outer faces, which must be exactly at right angles to each other, or the work executed upon it will not be square. The edge of that side of the chuck which is placed next the face-plate is rounded to the same radius as the plate itself, as the corners would be in the way, and might ncit clear the lathe-bed.

The work-a square block oLiron or brass-is represented at W. It is secured to the angle-chuck by two wrought-iron plates, l l, and two bolts, which pass through the latter, and through' f>uitable slots in the chuck. The slots in the angle-chuck are the same width as those in the face-plate, therefore the same bolts can be employed with both.

The upper surface of the angle-chuck upon which the work, vV, is fixed, must be sufficiently far from the centre of the face- plate to allow of the work being placed centrally. Of course that part of the work on which we intend to operate must project beyond the edge of the angle-chuck a little more than the aggregate thickness of the several cuts we must take to reduce the work to the required dimensions. The outer ends of the plates, l l, are supported by bits of hard wood, or metal of the same depth or thickness as the work ; one of these pieces is seen at T, fig. 38.

Before the work can be properly secured to the angle-chuck; its under face which is to rest thereon must be filed, or otherwise made perfectly flat, in order that it may have a firm bearing and also serve as a true "foundation," from which the four sides required to be at right angles to it can be wrought.

The first side having been faced, the bolts that hold the work must be slackened, and the latter turned round, the finished surface being placed against the face-plate. If the work be not thick enough to overhang the front edge of the angle-chuck sufficiently for turning, a parallel bit of metal can be put between it and the face-plate to make up the deficiency, but the piece thus introduced must be perfectly paralle1, otherwise it will throw the work out of truth. · The side parallel to that now resting on the angle-chuck, and on which the plates, l l, bear, may next be wrought, the side last faced being set upon the angle-chuck, and the original "foundation " placed towards the face-plate.



Four out of six sides are now supposed to have b.een completed, the first or original "foundation," which we filed true, and the three faced in the lathe. One of the two remaining sides must be set in the proper position for facing with a square, the back of which is applied to the face-plate, and the outer edge of the blade to the finished sides. If the bolts for fixing the work hinder us from using the square in this way, they must temporarily be removed, and a line scratched across the surface of the angle-chuck, and at right angles to the face-plate, by drawing a scriber or sharp-pointed · steel wire along the edge of the blade of the square. This line must be so pla~ed as to allow the centre of the work to coincide with that of the face-plate when the edge of the work is adjusted to the line. When this side is finished, the last may be set by the line, or in the manner previously described.

A circular lump of lead having a bolt-hole through it should be secured to the face-plate opposite the angle-chuck to counterbalance tbe weight of the latter, which, being out of the centre, would otherwise cause the lathe to run very irregularly. If the lead is fixed close to the edge or circumference of the face-plate, it will act with greater effect in counterbalancing the chuck than when situated near the centre; its influence therefore can in this way be slightly regulated.

The angle-chuck is shown separately in figs. 39, 40, and 41. Fig. 39 represents the surface on which the work is fixed, and the dotted line shows the thickness of the right-angled side that is bolted against the face-plate; in :Ilg. 40 is seen the outer edge of the plate, :Ilg. 39, and the inner side of that which is at right-angles to it; fig. 41 is an end view of the chuck.

Angle-plates, which are exactly similar to the angle-chuck, are freql1ent additions to the turner's apparatus, and some people employ them for carrying wood bearings, insteadofusing the frame, FF, fig. 31. The wood is required much larger than when fixed in a frame, as it must be secured with bolts to the front of the angle-plate. A suitable piece of wrought-iron plate, with a conical hole near one end, and a bolt-hole or slot at the other, for fixing it to the-angle-plate, serves as a boring-collar. As one conical hole only can be bored in this plate, a new plate must be provided if any variation in the work renders the former unsuitable. Angle-plates which are to be employed on the lathe-bed should be provided with a strip, similar to EE, on the poppet-head, :figs. 4 and 5, to prevent it 'shifting sideways, and insure its central position.

(To be continued.)


.Fi']. 31i.

',

~o \ / \., :p'

--,n@-/

H

E

.Fi!f .39.

DODD .Fig.33.

D D D Fz,g.1-1.

J?iy .. 44.

Pi!J. 45.

>

[To /ace Paqe 224. THE LATHE.

SrYme oJ th"se design& are copied.from Messra. II0Ztr.apfe1.'1 lat'ge wcwk, "Turning and :Meoha.nica.1 Manipulation/' wMch e%ceizent book we can cordiaZZg recommend to our readP.'l'a.


Fi~.4li.

Fig.17 .

.Fig.!!:!' .

.Fi~ .. 53.

THE LATHE. Eomeof these cleslgns are copied from Jlessrs. l!oltzapfei's large toork, uTurning and 1\-Ieeh.'\Jlic\.l Ma~ipulation/'

which excellent (nok ·we can cordlaUy recommend to our _read1rs.


224

THE LATHE, AND HOW TO USE IT; OR,

THE PRINCIPLES AND PRACTICE OF PLAIN' TURN:ING.

B Y T E M P L E T H 0 R 0 L D.

CHAPTER !IL-HAND-TURNING TOOLS.

OME of our friends may remember that we warned them, in the early pages of " Our Workshop," against purchasing " boxes of tools." Advice, though good, unfortunately is seldom well received, because people generally are in too great a hurry to become possessed of something that may have taken their fancy, and

accordingly resent any well-meant hint that was not solicited, especially if a caution be implied.

Even though gratuitous advice might be unpalatable to some folk, we should not hesitate". but bestow our counsels most impartially, and take the risk of offending a few. Happily, in this instance, however, there is no danger of anything we may say being taken amiss, simply because our readers will not get the advice for nothing, but must pay for it : this will insure its favourable reception.

A good lathe necessarily is an expensive machine, and we most strenuously counsel our amateur friends to take time, and watch their opportunities, and not buy the first lathe that may appear desirable, because ·"cheap." Except under peculiar circumstances, a "cheap lathe," like other cheap wares, is the costliest rubbish that can be placed as lumber in a workshop.

It should be borne in mind that although wood may more-generally be employed than metal during the earlier efforts of the young turner, yet, as he gains experience, works in metal will open a far wider field for practice and the exercise of skill.

The wood-turner's lathe, which usually is made almost entirely of wood, is far too primitive to be useful to the amateur, who necessarily requires his lathe to be as universal as possible. This, at first sight,



would appear to demand a large original outlay, but if the amateur exercises a little judgment, this to a great extent may be avoided. When choosing his turning-machinery he should adopt what may be called the "accumulative method," which admits of future additions being made to most of the apparatus and tools needed in the higher branches of the art.

For general plain turning in wood and metal, such as an amateur mechanical engineer is likely to practise, a neat, substantial lathe, made entirely of metal, is earnestly recommended, as being the best. The top or surface of the bed should be quite :flat, as the compound slide-rest, and other useful apparatus which hereafter may be procured, can be fitted to it with great facility and accuracy. The utility of the lathe, and the value of the slide-rest, will be greatly enhanced if the mandrel head-stock is furnished with an arrangement of toothed wheels called the back-rJ._ear, by means of which greater power and much slower motion is secured when turning metal works of large diameter, and without inconveniently reducing the speed of the fly-wheel. If, at the time of purchasing a lathe, you neglect to obtain one fitted with a geared headstock, the expense of afterwards substituting the latter for the simple pulley will be much greater than the extra cost of a lathe originally so fitted.

The size of the lathe is a matter that also requires consideration. If the ~entres are five inches above the surface of the bed, they will be sufficiently high to admit a piece of wood or metal as large as can conveniently be turned in a lathe driven by the foot. The bed should be from three feet six inches to four feet in length, and must be sup~ ported by two strong cast-iron standards, to which it is securely bolted.

The next and most difficult question, that of price, comes between the would-be turner and his ardent desire~a good lathe. We do not require to be told that very few of our readers can afford ten or fifteen pounds ; and this is a very moderate sum to give for a fair average lathe, unfurnished with a slide-rest, if purchased new of a good maker. .As it is idle for an amateur to entertain for a moment the idea of making a lathe for himself, he must patiently wait until he can find a second-11and article within hi~ means.

Excellent lathes and other tools may often be bought for half of their vaJue, at sales by auction; but the greategt caution must be exercised in order to avoid the unpleasant consequence of a very bad, instead of a good, bargain. Do not; trust to your own unaided judgment, but take the advice of some friend who has had experience in such matters; and if you are unacquainted with any one qualified to h!l}p ;ron? i~ yvtH \it'

Q


226 · THE LATHE, AND HOW TO USE IT j OR,

economy on your part to give a pl.·actised metal-turner or engineer a trifle for a practical opinion on the merits of your proposed purchase.

Favourable opportunities for buying really good second-hand machinery are by no means rare. Not long since, a friend of ours wanted a good lathe, and, as usual, cheap. We recommended him. to watch for advertisements of sales by auction of engineers' tools, and promised t<> give all the assistance in our power. His patience, in this instance, was not very sorely tried, and he obtained, for little more than halfprice, a new screw-cutting and universal self-acting lathe, that had been made expressly to meet the requirements of amateur mechanical engineers. We are aware that this was an unusually fortunate circum· stance, but know that on several other occasions very satisfactory purchases have been made, and can speak, therefore, from experience.

The gouge, shown in two views, figs. 42 and 43, is employed by the · wood turner to remove the irregular or rough exterior of the work, and to reduce it to the circular form previously to applying the chisel. The body of the gouge somewhat resembles a reed or quill split in half in the direction of its length, or may be compared to a hollow chisel : a transverse section is seen at S. The cutting-edge is ground exteriorly and obliquely to an elliptical figure, and differs in shape from the carpenter's gouge.

The turning chisel, figs. 44 and 45, unlike the carpenter's chisel, is ground with a double bevel, or from both sides, and the cutting edge is not at right angles to the sh~t, but obliquely, as in fig: 44.

The turner's gouges and chisels vary in width from one-eighth inch t<> two inches, and as they are not used with force, or driven with a. hammer, no shoulders are formed on the tangs, as the latter are not likely to sink too deeply into or split the handle. Wh.en the gouges and chisels exceed one inch in width, they generally are fixed in long handles, as in the figures, which measure, including the tools, from fifteen to twenty-four inches; the smaller tools have shorter handles, from eight to twelve inches in length over all.

The same tools cannot advantageously be employed upon both hard and soft woods, and the tools suitable in each case are somewhat differently applied. The bevels~of the cutting edges of tools used for turning soft wood are ground at an angle varying from twenty to thirty degrees, and those for hard wood are more obtuse, being usually about forty degrees. The angle at which the cutting edge is formed should be regulated by the nature of the substances to be wrought, and it may be accepted as a rule, that the harder the material the more obtuse, and the softer the mor~ acute must be the angle of the bevel. This principle is



borne out both in carpentry and turnery, but is carried to a much· greater extent in the latter when metal work is executed. ·

The position of the gouge for turning soft wood is represented in fig. 46. The centre of the back or convex part of the gouge, G, lies upon the rest, R, which is su:(ficiently raised to allow the bevel indicated by the dotted line, a, b, to lie upon the circumference of the cylinder,. W, or be nearly as a tangent to it. The handle of the tool is grasped near the end in the right hand, the thumb being extended as seen in fig. 4 7 ; and if the cut is to be light, the left hand is placed under the convex part of the gouge, and the fingers are closed round it, their tips resting on the right hand side-edge, while the thumb presiles upon the other to keep the instrument closely down to the rest. When the cut is m;msually heavy, or the work much out of truth, the hand generally is placed over, instead of under the shaft, and the fingers are closed beneath it, thus enabling the operator to hold the tool more securely, and, by pressing heavily upon it, prevent it slipping back when a knot or any irregular portion of the work comes suddenly in contact with its edge.·

Sometimes in "roughina~out," when it is unnecessary to traverse the gouge far along the rest, or in the direction of the axis of the work, the fingers of the left hand are clasped round the neck of the rest, just clear of the work, and the thumb is placed across the top of the gouge, which is thus clamped powerfully down upon the rest. The edge of the tool is made to take effect in the lengthway of the work, by moving the handle alternately to the right and left, the shaft swivelling as it were on a centre under the left thumb, which is kept stationary. In this method the cutting edge of the tool moves in a small arc of a circle, but no inconvenience arises from this circumstance during •the first stage of the work, and, if desired, a short rectilinear movement can be imparted to the instrument by alternately bending and extending the thumb.

Under ordinary circumstances, and after the wood has been turned. 1·oughly circular, the gouge must be traversed steadily along the rest in order to make the surface of the work as regular as possible, before applying the chisel. Sometimes when using a tool fitted with a long handle, the end of the latter is tucked under the right arm, by which it is :fifmly pressed to the side, and the hand grasps the handle near the middle. When the end of the.handle is held in the right hand only, the latter must be kept close to the workman's side, the tool being moved along the rest by the left hand. · ·

The application of the gouge for facing fiat surfaces differs somewhat from that already described for ordinary cylindrical turning, · The side

Q 2



edge of the tool is placed upon the rest, the convex or rounded side, which ordinarily lies thereon, being towards the surface about to be wrought. The handle of the gouge is held nearly horizontal, and at first the bevel of the cutting edge is allowed to touch the work, but before the tool can take effect, the handle must be inclined sideways until, by slightly raising the bevel from the work, the cutting edge is enabled to operate as the instrument is gradually urged from · the circumference to the centre of the work.

When the gouge is employed to face the bottoms or interior planes of hollow works, such as shallow cup-chucks, boxes, &c., it is applied in much the same manner as just described for external fl.at surfaces. The shaft or blade of the tool, however, is more inclined horizontally than in the first operation, and the cut is begun at the centre instead of at the circumference or margin of the work. The middle of the elliptical edge or nose of the gouge is pressed forward until a shallow hole, equal in depth to the intended cut, has been bored ; the instrument is then swept across the work by lowering the handle, and at the same time twisting it round one-fourth of a revolution. If the manipulation is properly performed, both the side edges of the gouge will lie upon the rest, when the entire surface or plane has been traversed by the cutting edge, and the tool· assumes the position shown in fig. 47, only the rounded or convex part of the shaft will be uppermost.

In fig. 48 it will be seen that the position of the chisel for turning the cylinder, W, when of soft wood, is the same as that of the· gouge when similarly employed. The shaft of the chisel, however, is not hekl strictly at right angles to the axis of the work, but slightly inclined in the opposite direction to that in which it is being moved along the rest .. In fig. 49, which is a longitudinal view of the work, the chisel, R, is supposed to be passing from left to right, and L from right to left. The oblique position of the cutting edge prevents its taking too wide a bearing on the work, and also enables it to act with great smoothness, ..entirely avoiding any risk of "tearing up" the fibre of the wood, which ·.would be very likely to happen if the edge were applied parallel to the _axis of the work. The edge may be ground square across, but the blade __ must then be held in a more slanting position sideways, to keep· the ..corners of the tool from digging into the work;

Those who are acqtiainted with the construction and use of the joiner's planes will observe in the turner's chisel the same principles as exist in the skew-rebate and fillister. In these planes the irons are set obliquely in the stocks, and their edges take effect on the fl.at surface in much the same manner ·as the slanting edge of · the turning chisel, when applied to cylindrical work in the lathe.



The manner of holding the chisel when turning cylindrical work in soft wood is exhibited in fig. 50. The handle is held in the right hand, which must be kept close to the person, as u;: using the gouge, and the palm of the left hand should be placed on the blade, and the fingers closed underneath it.· The chisel is traversed along the rest by moving both hands simultaneously, and sometimes also by inclining the body a little in the required direction. Considerable practice is necessary in the manipulation of the chisel, and at first it will be found difficult to remove the wood in their uniform shavings, and to-make the work truly circular.

Fig. 51 represents the manner of holding and applying the chisel for turning or facing the end of the work. The longer side edge of the tool is placed on the rest, and the chamfer or bevel of the cutting edge is brought into agreement with the intended plane by holding the chisel in a slanting position sideways. The handle-which, as usual, is grasped in the right hand-is lowered until the point of the chisel is raised nearly to the level of the centre. The blade of the chisel, as may be seen in fig. 51, lies in the hollow of the left hand, the fingers of which are closed r()und it, the thumb bearing on the upper side-edge. The rest is HO

placed as to enable the turner to hook the middle joint of his forefinger under it near the end, and thereby obtain greater control over the tool, which, being supported only on a narrow edge, is apt to swerve from its proper course, and damage the work. As the point of the tool is thrust from the margin to the centre of the work, a very thin slice of wood is detached, which curls over towardsLthe back-centre, as it is displaced by the outer chamfer of the chisel.. The chisel must be he!d very firmly, and kept rigidly to its work, especially at the commencement of the cut, 11s .it is very apt to be drawn over the circumference of the wood, in which it will make a deep l:lpiral or screw-like ·groove that may unfit it for the purpose for which it was intended. This is the most difficult manipulation of the chisel, and even after considerable practice a little want of caution may cause the chisel to slip and rip off the edge or corner of the work, and entirely destroy its artistic :finish.

When boring work, the rest is placed across its face a little below the centre, as shown in :fig. 52. The tool is held horizontally, and the thumb of the left hand is placed on its upper edge, to keep the instro~ ·

ment steady on the rest, while it is thrust forward by the right hand, The cutting-edge of the tool should be on ·a level with the centre ; its action, however, is not impeded, if only slightly raised above the centre, but, if lowered, its operation is sooner obstructed.

If the wood is very lmrd, the tool is apt to :fly from the work towards



the centre, but it can generally be restrained by hooking the fingers of the left hand under the rest, and pressing more. forcibly on the instrument with the thumb.

The position of the tool when boring is the same whether the wood be hard or soft, and its action is that of a scraping rather than a cutting instrument. Hard-wood tools are applied nearly horizontally as shown in fig. 53, and are formed with a single bevel like a firmer chisel, but the angle is much more obtuse, varying from about 40 to 60 degrees. They remove the material by scraping it off in short thin shavings, and are much more suitable for hard-wood turning than the double-bevelled chisels, which are, however, sometimes used upon the hardest woods, and are applied as in fig. 50. An ordinary soft-wood chisel is too keen for turning the harder kinds of woods, and its edge very soon becomes notched ; therefore two sets of tools should be provided, and ground to the angles already recommended for each variety of work. Too much attention cannot be given to this branch of the subject, and our readers will soon discover that the angles at which the cutting edges of their tools are ground, influence most materially the production and· finish of the work.

We shall have occasion, when speaking of fixed or slide-rest tools, to notice the angles which in practice have given the , best results, and therefore will not enlarge at present.

(To be ccntinu~d.)


FIG. 54. FIG. 56, rm.sz FIO. 58, FIG. 59, FIG. 69,

FIG.60. FIG. GI. rlG. 62,

FIG, Ga. FIG. 64. FIG, GS. FIG.66..

~-

flG.73,

FIG.6.7.

FIG,68.

~~~~~~~~~~~~~~~~~~~~~~~--~~~

THE LATHE: AND HOW TO USE IT.

3 B

I·, :<


( 735

THE LATHE, .A.Nb HOW TO USE IT ;

o:R,

THE PRINCIPLES AND PRACTICE OF PL.A.IN TURNING.

(ContinuPit from page 231.)

CHAPTER III. (continued).-HAND-TURNING TOOLS.

N addition to the tools for turning soft wood figured at page 225, we have the hook-tool (fig. 54); which is used for hollowing out the insides of boxes. ·Like the others, it is chamfered on both sides. Fig. 55 represents the parting tool for rapidly cutting through the work at right angles to its axis. The teeth of course

give it a saw-like action. There is also another tool of the shape indicated in fig. 56. It is of great use in trimming up the ends of the work. There are many others of almost an infinite variety of shapes and sizes sold· by the various tool-makers, each manufacturer having his set of patterns, but the young amateur should be warned once for all against the needless multiplication of tools. Those enumerated are quite enough for all ordinary purposes, .indeed many good workmen content themselves with the gouge and chisel only. .

For hardwood, ivory, bone, and other materials of a similar description, a more extensive set of tools will be required. As we have already mentioned, they differ from soft wood tools in having only a single bevel, the beveled side being always kept downwards when: working. The angle of the bevel is also greater, being from 40° to 60° or 70°, instead of from 20° to 30°: The angle, too, at which the tool is held is also much increased, as may be seen in fig. 53. In: fact, the action of the tool is no longer that 6f a: cutting instrument, the material being scraped away in more or less powdery chips, rather than shaved oft' in long clean slices~

For roughing out; a g'Oti:glr ·ground to a pretty obtuse angle, and l!ield almost at right angles to the work, is generaHy used whe:ii th!r:inaterial



belongs to the softer portion of the great hardwood family. For roughing out ivory the point tool is used. It is represented at fig. 57. It is of course used with the beveled side downward, although it is shown in the cut in the reversed position, for the sake of clearness. This remark will apply to all the drawings of hardwood tools.

Figs. 58 and 59 show the form of the right and left side tools. They are used for a variety of purposes, such as trimming up the ends of the work, hollowing out boxes, and so on. If the work in fig. 52 were hardwood, the side tools would be called into requisition. Figs. 60, 61, and 62 give a representation of the inside parting tool, the use of which will be explained further on. They are made with the angle piece at the end of various sizes. There should be at least three of them. The outside parting tools are made from thin Hat pieces of steel, slightly hollowed out and ground flat at the cutting edge. The point tool may be used for giving almost any form to the surface of the work, but many amateurs are in the habit of using shaped tools as shown in figs. 65, 66, 67, 68, and 69. The true workman should render himself independent of these aids, and form all his mouldings and hollows with a sharp, keen point tool. By gaining early the necessary skill to design and execute mouldings of various and complicated patterns, he ·will find his fancy much more unshackled, thari. if he accustoms himself to the use of tools giving mouldings and hollows of a fixed size and shape.

CHAPTER IV.

FIRST PRACTICE.

HA YING given a very full description of the hand-turning lathe, and the tools to be employed with it, we will now suppose the amateur

to have bought and set up his lathe, and to have laid in a stock of tools. He will also require a few saws, a mallet, two or three hammers, a small chopper, an old chisel or two, and a spokeshave for smoothing down the work before putting it into the lathe. A jack-plane and half a dozen gimblets and brad-awls will complete his assortment of ordinary carpenter's tools.

For special use with the lathe he will require a set square, a pair of compasses, a pair of inside and outside callipers for taking diameters and thicknesses, and an oil-can.


738 THE LA.THE, A.ND HOW TO U$E IT ; OR1

The engineer's square (fig. 70) consists of a flat steel rule, genemi:lly marked with inches graduated to sixteenths, upon which slides a piece of brass or gun-metal at right angles to the sides of the rule. It is fixed in the desired position either with a screw or else by means of a strong spring inside. It is used for a great variety of purposes, such as for testing the squareness of t.b.e ends of your work, measuring the depth of the interior of boxes, &c.

Fig. 71 is an oil-can. It is simply a tin cone with a nozzle screwing off and on, and pierced with a fine hole. The bottom is made of very thin metal, and is slightly convex. It is used by lifting it with the first and second finger placed just under the nozzle, the thumb being underneath ready to press the slightly :flexible bottom when necessary. By reversing the cone, and squeezing the bottom slightly with the thumb, a small stream of oil is ejected from the nozzle. The best lubricant for lathe purposes is neat's foot oil, which may be obtained at the :tool shops. It has the property of remaining liquid without clogging ::for a longer period than any other in common use. ·

Fig. 72 represents a pair of double callipers, or in-and-out callipers, :as they are generally called; they are so made that when open the ends .a, and b are the same distance apart as c and d. The screw at e ought to work rather stiffly, so that in gauging a cylinder or hollowed out spaces, the arms may retain their proper distance apart. Some turners prefer to have separate callipers for measuring inside and outside work, but the amateur will find the double pair the most convenient.

Some soft cotton rag, a stiff brush for cleaning the lathe from chips, and a few sheets of fine glass paper will complete the amateur's equipment.

In commencing work the first thing to do is to examine all the bearipgs and centres of the lathe, especially the points or friction wheels upon which the crank axle runs. As a rule all centres should be looked to every day before beginning work. There are two faults in the management of centres and bearings that most amateurs are very prone to commit, namely, screwing them up too tightly and oiling them too much. The first will speedily put the parts out of truth, the second is wasteful, slovenly, and unnecessary. Little and often should be the rule for oiling.

Having satisfied yours~lf that every part of the lathe is clean and in proper working condition, you must first practise with the treadle until you succeed in setting the whole in rapid motion with either foot, without moving the upper part of the body, This sound.a an easy thing to do, but except the amateur has been used to working a treadle, he will



find it more difficult than he would imagine. The consequence of moving the upper part of the body every time the tre::i-dle is pressed, is. to cause a corresponding advance in the tool that is being used, and a consequent irregularity in the woxk.

The next thing will be to take a piece of dry pine or willow, about ten inches long and two inches thick. Work it roughly into a cylinder with an ordinary chisel or spokeshave, taking care to saw off the ends as square as possible. With a pair of compasses mark the centre of each end as accurately as you can. Screw the prong-chuck (figs. 12, 13, and 14) on the lathe, and press upon .it the rough cylinder, taking care that the prong is inserted exactly in the centre you ·have marked with the compasses. The prong of the chuck should enter the wood sufficiently deep for the side edges just to come into play. Holding the cylinder in your left hand, bring the sliding poppet-head with its centre within a quarter of an inch of the centre of the work. Screw up the poppet-head from beneath so that it is perfectly fast and immoveable, and by means of the screw advance the centre so that it enters the wood about the eighth of an inch. You now have your rough cylinder mounted in the lathe. You may, if you like, just touch the back· centre with oil to ensure perfect freedom of rotation.

Move the rest to within half an inch of the work, and screw all up tight, taking great care that the rest is parallel to the surface of the work, and a little above the line of its axis. Then with the gouge rough o.lf as much of the surface as you find necessary to bring the work tD the state of a perfect cylinder. The gouge must be moved along carefully and firmly, in a straight line, taking off as little as possible each time. Having satisfied yourself that your work is pretty true by the eye, proceed to test it with the callipers. It may here be noticed that, unlike ordinary compasses, callipers are altered by tapping the inside or -0utside of the legs on the lathe bed. You will possibly find that your first attempt to form a perfect cylinder is a failure, tha;t one end is smaller than the other, or that the centre is larger than either. You must not be discouraged at this, for it is only what every turner has had to put up with at firs!;. If you find your cylinder out of truth, measure the smallest part with the callipers, and reduce the rest to that size. When you find that the cylinder is almost true from end to 4Snd, ·proceed to smooth it down with the chisel, taking care to work as much as possible with the half of the tool that is nearest to the obtuse angle. If you attempt at first to even touch the work with the i-:harp point, you will infallibly dig into the wood, and either break the chisel, .spoil :the work, or throw the cylinder out of the lathe. Having made a

3 B 2



cylinder to your satisfaction, you next proceed to face up the ends, . using the obtuse angle of the chisel to finish up with. You will find

squaring up almost as difficult as making a perfect cylinder, especially at the chuck end of the work, and it wiU be only by using the square continually that you will succeed. It is hardly necessary to warn you to be careful in leaving sufficient waste stuff for the work to run upon at each end. These waste pieces are carefully removed with a fine saw after the work is finished. In squaring up the ends, you will find a great difficulty in keeping the angle clean and sharp. Even with the greatest care, pieces will chip out: Never mind if they do, pine and willow are both cheap, and you can begin a new cut without any very <li<lastrous consequences. When yon find your cylinder is perfectly true from end to end, that the angles are sharp and clean, and that the faces are true and square, you can smooth up the work with a piece of fine glass paper; finishing up with a close handful of the shavings from the wood itself.- If you have succeeded in complying with all the conditions

.:. FIG. 74. +-e ~ ----- --- --- . ----- - ------ -r-"

--·--------------··------ -1'L-

___ ---- ----------------l-2

-·-----------·-----------J------- -- -------------------~--

i f

. ________________ J ... i

we have named, yoR may congratulate yourself on having passed the first great pons asinorum of the art, that of turning a perfect cylinder with square faces and sharp angles.

Fig. 7 3 will give the young workman an idea of the shape to which the rough cylinder is reduced just before sawing off the waste ends. The light line indicates the rough pieces of wood, the black one the nearly-finished work.

In making our cylinder -as the young workman will no doubt have

~ noticed-we have taken no heed of _________________ J__ its size, either in length or diameter ;

--------···---------r-- onr next lesson ought, therefore, to be

1 directed towards gaining some skill in ith

shaping our work to . definite dimen-s10ns. A child's skittle of the form indicated in fig. 7 4, in which every

part has a definite size, will be an excellent example to begin with. .A cylinder is first turned out of a rough piece of pine, or willow, and the length from A to B i<> marked on it with a parting tool. At the first attempt it would, perhaps, be as well to provide for any little accident to the corners, by making the marks a quarter of an


THE PRINCIPLES AND PRACTICE OF PLAIN TURNING. 7 41

inch farther apart than necessary. The callipers and square must be called into continual requisition, and great care will be needed in tu ming down the neck of the skittle not to chip the wood. The two hoUows in the body of the work may be formed with the parting tool, and filled up while in the lathe with red or black paint. Tl1e two mouldings on the neck are semicircular. The learner should design for himself several other skittles of different sizes, working them accurately to scale. He should -also, preparatory to commencing with hardwoods, learn to make and fit a box and its cover with accuracy.

Take a piece of willow, or pine, and turn from it a neat cylinder, three inches in diameter, by three in length. Before cutting off the waste ends, cut it almost in two pieces with the parting tool-say an inch from either end. The parting tool should be used with great care, and when the cylinder is cut through to within-say an eighth of an inch-the work should be taken out of the lathe, and the separation completed with a fine saw. The waste ends should also be sawn oft We have now two cylinders, the larger of which will form the box, and the smaller, the lid ; the larger piece is next fixed accurately in the cup chuck, and the inside carefully turned out with the gouge and chisel, the rest being turned round to face the work. The rim of the box where the cover shuts on, is then formed, and the piece for the cover is _substituted in its place. No doubt the first time great difficulty will be felt in making the cover fit the box, the chisel somehow or other always taking off a little too much. Wh!=n this is the case, you must sacrifice, the size of your box by turning off the rim and making a fresh one. You can, if you like, ornament your work with V shaped rings, or, if it is thick enough, with mouldings. The bottom should be made slightly concave on the outside, so that it may stand better. When complete, place it in the cup chuck once more, and finish it up with fine glaHs paper, and its own shavings.

Having succeeded so far, it is only fair to suppose that the tools you have been using have become blunt, broken, or otherwise rendered unfit for use, we shall therefore pause in our instructions for using the lathe, ~md devote the next chapter to a description of the best method of keeping tools in order.


742 THE LATHE, .AND HOW TO USE IT ; OR,

CHAPTER V.

SHARPENING TOOLS.

WHEN the tools come from the makers, they are generally in a

half blunt condition, except the manufacturer has received special orders from the purchaser to have them properly set and sharpened. It will, therefore, be a good plan for the beginner to have -bis tools properly sharpened at starting by a competent workman, that he may see what a really sharp tool is.

It is hardly possible to over-estimate the value of keeping one's tools in a perfectly sharp condition. If the skill of the carpenter is known by the neatness of his chips, the turner's ability may be estimated with still greater certainty by a glance at the shavings that have come from his work. At the very beginning tlrn amateur must accustom himself never under any circumstances to work with a blunt or notched tool. A keen, well-set chisel will cut through the work with rapidity and truth, leaving a natural smoothness and polish on the wood which no amo-µnt of glass-papering can imitate, whereas a blunt or notched instrument is not only much slower in its action, but the round is generally untn1e and rough. If one side of the wood happens to be harder than the other, the blunt tool will naturally act less upon it than on the softer portion, causing a corresponding deviation from the circular form.

The young workman should make it an absolute rule · never to begin work without giving his tools a touch on the oilstone.

In sharpening a chisel or other turning tool, there are two distinct operations to be gone through. First, the primary bevel giving the shape to the tool is formed on the grindstone, after which a secondary bevel is produced by a Turkey or other oilstone.

----------il

Fig. 7 4, which is an enlarged diagram of a soft wood chisel, will illustrate this. The bevels in the direction a b and c dare formed by the



grindstone, whilst the others following the lines e f and g Ii are those given by the oilstone. Figs. 7 5 and 7 6 show the same thing in the case of tools for harder woods and ivory.

The primary bevel is formed by holding the tool . perfectly steady, against a revolving grind- FIG. 75•

stone, taking the greatest care not to alter the angle at whfoh it is held. The slightest deviation will cause a new face to be formed, and :finally, instead of having a flat, or if the grindstone is small, a slightly concave b~vel, an irre-gularly rounded surface is formed, which cannot FIG. 76 ,

be properly set, and will never produce a clean cut. The hands must be moved from side to side as the bevel is formed, otherwise one por tion of the grindstone will be worn more than another. It is during this traversing motion that it is most difficult to keep the tool at the proper angle, however practice ·.vith soft iron in the :first instance will soon enable the learner to produce a clean fiat bevel. There is also great danger of moving the tool on its own axis, and so producing T01mded corners to it instead of sharp ones ..

T.he grindstone is too familiaT an object to need much description. They are generally

l'IG. 77.

mounted so as to dip into a trough of water, but they should never be allowed to remain in it, as the part immersed would become softened, and either break or wear away unequally. A grindstone should never be used dry, as it would not only give the tool a rough edge, but there might be sufficient heat generated to soften the steel and destroy its temper. .

Grindstones are made from a sharp gritty sandstone found in different parts of England. They are generally turned by a winch, and in most cases should revolve against the tool, and not away from it. They are also :fitted with a treadle, but we should strongly advise our young friends to purchase one with a winch that can be worked by any com panion that may happen to be near, as it leaves both hands and feet at perfect liberty.

The great point in holding the tool steady is to press the arms and elbows well against the sides, the rest of the body being kept. .firm and motionless.


74.! THE LATHE, AND HOW TO USE IT j OR,

Having succeeded in making a perfectly :flat bevel of the proper angle, it only remains to form the secondary .bevel on the oilstone. The best stone for this purpose is the white or black Turkey stone, a close compact mineral found in the interior of Asia Minor. The black variety is slightly harder than the white.

The tool should be held perfectly steady, and passed over the stone some twenty or thirty times. The same difficulty arises here that we met with at the grindstone, that of keeping the tool at the proper angle and producing a single flat bevel instead of several running into each other. The amount of secondary b!lvel to be given to the tool is very slight. In figs. 74, 75, and 76 it is necessarily much exaggerated, in order to make matters plainer. The tools shown in figs. 67, 68, and 69 are sharpened with a slip of oilstone applied to them . in the manner of a file. They are very difficult to keep in order, and we repeat our advice to our readers to exclude them from their stock of tools. The inside of the bevel of the hook tool is sharpened in this way. It will be hardly necessary to warn the amateur against leaving his oilstones uncovered when not in use, as they soon become covered with gritty particles. It is, however, a very common practice to do so.

Oilstones are always let into a solid piece of mahogany or other strong wood, a coyer of the same material being hollowed out to fit the stone. A few Rharp pins are sometimes driven into the bottom of the block containing the stone, so that it may be fixed immovably on the bench while being used.

Besides black and white Turkey stone, there are several others that may be used, but for giving a fine edge, there is nothing equal to Turkey stone. Arkansas resembles it greatly, but it is more irregular in its texture. Charnley Forest stone, Water of Ayr stone, and Welsh hones belong to the slate family, and are consequently much softer than either Turkey or Arkansas.

Very fine tools are sometimes sharpened in the lathe on a lap or disk of metal composed of lead with a tenth part of Rntimony melted with it, to give it hardness. It is generally mounted on a brass chuck, the grinding material being fine emery powder mixed into a stiff paste with tallow, and smeared on its surface. The tools are held against the face, being easily kept ste.ady on the rest at any angle that may be necessary. In using it, great care must be taken that none of the sharpening paste drops on any of the working parts of the lathe, or they will wear unequally .

. Some very particular turners finish their tools on a strop rubbed with emery powder and tallow, but this is hardly necessary except for any fine work.



CHAPTER VI.

HARDWOOD TURNING.

ONE of the first things the amateur ought to do as soon as he has gained moderate proficiency in his art, is to make himself a set of

tool handles. Those sold at the shops are generally mounted in beech, but the harder woods are more proper for the purpose. The other day the author saw a set of tools mounted in first-rate style by an amateur turner who had only been at work for a week or ten days. The handles were all made to the same pattern, but the woods for each class of tool were different, so that when they were lying about the bench, a particular chisel or gouge could be found at once. Thus the gouges were all mountecl in box, the chisels in rosewood, the parting tools in walnut, and so on.

The first_thing to do is to procure a piece of stout bras~ tube about half or three-quarters of an inch in diameter. A length of this is driven ori to a piece of pine or beech that has been turned in the lathe to fit it. The whole is then mounted between the centres, the centre chuck, figs. 9 and 10, and the carrier, fig. 33, being used for the purpose. The tube is next cut into rings about a half or three-quarters of an inch wide with the hardwood point tool or a triangular file, ground down to a cutting point, and, if necessary, they may be brightened with emery paper. These brass rings serve the purpose of ferules, and are driven on the upper part of the handle, to prevent it being split when the tool is driven in. It would be as well to make two or three dozen of these rings, as they are useful. .A_ piece of wood-box is the best to begin upon-having been chosen, the centre chuck is replaced by the prong chuck, and a small portion of the end nearest the mandril is turned down to fit the ferules. The body of the handle is then turned to any shape the amateur may like to use. It will be excellent practice to turn several different patter:ns at first, and find out for himself which one fits his hand the best.

If the young workman has practised much with soft wood he will find it rather difficult at first to adapt the position of his tool to the material he is at work upon; indeed, in the trade it is very seldom that

. we find a workman excelling both in hard and soft wood turning, the treatment of the two classes of material in the lathe being so different. If it is a piece of boxwood he is at work upon, he will find that the inequalities in the rough piece will continually drive his tool from its



position. This must be remedied by firmly grasping the boss of the hand rest with the left hand, and holding the tool tightly in its place with the.thumb. Box being of medium hardness: the angle at which tlie tool is ground should not be too obtuse.

When finished, the work should be smoothed with a piece of fine glass paper, made finer as the process proceeds by being rnbbed against another piece. The finishing touch is given with a rag very slightly moistened with linseed oil. Some tumers use a piece of waxed cloth, wetted with a few .drops of turpentine, but·if the tools used have been property sharpened, very little artificial polishing will be necessary.

Tool handles are of various lengths, those for soft wood being often as long as fifteen or eighteen inches, but hardwood tools do not require their handles to be longer than eight or nine inches. The young workman should begin with the short ones, as they are the easiest to turn. If the pattern is at all complicated, it will be well to make what is called a template. The pattern is cut out in section from a piece of sheet zinc or tin, and used to test the tn1th with which the worker adheres to his pattern j it is a good plan to rub the edges of the template with chalk, so that when it is applied to the work, the prominent portions which require reduction may be more· easily discovered.

The· amateur should next set to work to make himself a series of boxwood chucks for holding the different objects that he may have to turn, and which will not fit in the cup-chuck.

When he buys the lathe he should provide himself with a set of screw taps for making hollow screws of the same size as that 011 the nose of the mandril. A piece of boxwood of suitable dimensions is then placed on the screw chuck, fig. 15, and turned to a cylindrical form, the encl being carefully squared, a hole is next made in the centre of the flat portion, and with the parting tool, the hand-re~t being turned round to face the work. The hole should be of such a size a.s to admit the small encl of the smallest screw-tap. The work is then removed from the lathe and fixed in the vice with the hole upwards. The formation of a thread with the screw-tap is a very simple operation. The smallest is inserted in the hole to be screwed, and turned round by means of the handle, a slight downward pressure being given at the same time. It is of course evident that the tap must be kept perfectly upright, or the screw will be crooked. When the smallest tap has reached the bottom of the hole, the two others should be used to com~ plete the screw, when it is finished it should be fixed on t.he nose of the mandril, and a hole, say au inch in diameter, cut in its face, the sides and bottom of the hole being made very square a;nd true. Half-a-dozen



of these, .with holes of different sizes, varying from half an inch to three inches in diameter, should be made, the holes being afterwards enlarged. to fit the work. Fig. 18 is an excellent form for a boxwood cupchuck.

Having provided himself with a set of tool handles in rosewood, walnut, and box, the amateur may next try his hand at something harder, for instance, a piece o,f sound black ebony. A snuff box will make a very good object for first practice. Ebony is one of the hardest woods we possess, almost rivalling ivory in its closeness of gTain and sui;iceptibility of polish.

A suitable piece having been chosen, it may be worked into a rough cylindrical form with an old chisel or gouge, and inserted in a boxwood chuck. The end to the right must be turned perfectly cylindrical and square, making its diameter a shtllde larger than three inches. Another chuck is now inserted in its place, and a hole turned in it to fit the finished end of the ebony cylinder exactly. The rough end is next completed, and the piece for the cover cut off. When we were working in willow and pine, it will be remembered that we reduced the inside of our box to a mass of shavings, but with a hard wood like ebony this would take a long time, besides: being very wasteful. The following method of removing the interior of the box is the simplest and easiest.

Having decided on the depth of the box, you cut a gToove with a pointed parting tool almost to the lowest point. You then insert the smallest of the square.headed inside parting tools (:fig. 62), cutting away with it as far as it will go. The second size is then used, after that the third, and so on until thi:i piece drops out. The figures 79, 80, and

FIG. 79, FIG. 80.

81 will illustrate this. If the box is too broad for the largest inside parting tool, a hole may be made in the middle to allow of its being used both ways. Fig. 82 will illustrate this. If the cover is too shallow to need being cut out without wasting the central piece, the


748 THE LATHE, AND HOW TO USE IT ; OR,

interior may be removed in chips. The rest of the work is performed in the same manner as when working in willow.

When the young turner has so far conquered his work as to be able to produce almost any form. he pleases, he should commence working in ivory. Ivory, as he will soon find out, is a very expensive material, and, consequently, not well adapted for trial work. One of his first essays in ivory turning ought to be a sphere. He begins by making a cylinder, whose diameter is exactly equal to its length. The middle of the cylinder should be marked with a very fine red line-a little vermillion water-colour is, perhaps, the best material for the purpose. The centres

FIG. 81, FIG. 82.

of the ends should also be marked with a small dot in the same manner. A. semi-circular template should next be cut out of a piece of tin plate, and its edge slightly smeared with a little lampblack and oil. The cylinder being fixed with perfect truth in the boxwood cup chuck, the corners are carefully and slowly turned down, the template being constantly applied as the work advances. The greatest care must be taken not to efface the red marks. When you have turned one hemisphere to your liking, reverse the work. You will fin~ some difficulty in centreing it properly in this instance, for the part that fits into the chuck is no longer cylindrical but spherical, the hold, consequently, that the chuck has upon it is extremely slight. You will now see the use of the red dots at each end of the cylinder, and it will only be by great patience and very gentle taps that you will be able to centre your work.. If the chuck is slightly chalked, you will find it hold the ivory better. If you succeed in making your ball truly spherical in every direction at the first, or even the sixth trial, you may congratulate yourself on doing what very few amateurs ever accomplish. It sounds very easy when described, but in practice it is very difficult, and the amateur who can


THE PRINCIPLES AND PRACTICE OF PLAIN TURNING. 7 4:9

turn an ivory or hard-wood ball with even a moderate degree of exactitude may call himself a very clever turner.

Cutting male and female screws in hard wood and ivory is the next branch of the art of turning ·to which the young workman ought to apply himself.

There are two kinds of screws, male and female, or external and internal. Thus the thread cut on a bolt is a male or external screw, that formed on the inside of the nut is the female or internal screw. Screws are formed in two ways, either by the use of taps and dies, or in the lathe by screw-cutting tools. As screws are rarely formed on ivory or hard wood by taps and dies, it will be as well to leave our description of them until we come to metal turning. The formation of a female screw by means of a tap has been already briefly described when treating of boxwood chucks at the beginning of this chapter, but it will be much better if the amateur will procure for himself a screw-cutting tool to :fit the threads on the nose of the mandril, and form his screws in the lathe instead of by means of taps. Figs. 83 and 84 are screw-tools for internal and external work. They are made by pressing a piece of soft steel against a master tap revolving on a lathe, the master tap being a hard steel screw, with longitudillal grooves cut in it, so as to form sharp cutting edges. A counterpart of the

Fm. 83. Fm. 84.

screw is soon formed on the tool, which is afterwards hardened, tempered, and sharpened, by being ground upon its face.

The action of these tools is as follows :-The cylinder or hollow upon which the screw-thread is to be formed

is :fixed in the lathe in the most convenient way, and the screw-tool held gently against it. The teeth of the tool, which are slightly askew, cut a continuous spiral groove on the surface of the work, which will be an exact counterpart of the original screw from which the tool was formed. The great benefit to be gained in using the screw-tool is, that you can form a thread upon outside or inside work of any diameter, whereas when using taps and dies the diameter must be in all cases identical.

It is somewhat difficult at first to start a thread cleanly. The screwtool is held steadily, but not too firmly, on the rest at the right hand end of the part to be screwed. The lathe should be worked somewhat slowly, and the tool aclvanced very gently. As i>OOn as the tool touches



the work, it should be traversed from right to left, so as to follow up the spiral made by its teeth. The spiral line formed at first should be the merest scratch, and as soon as it is made examine it minutely, to .see if it is perfectly regular. If it is not turn it out and try another. If, however, the spiral is regular, increase its depth with the screwtool to the desired amount. The inside screw-tool is used precisely in the same manner. There is a peculiar knack in using the screw-tool that is very difficult to describe intelligibly. In fact, it is as hard to put into words a8 the way of making leg-hits at cricket, both operations being most easily learned by a practical lesson or two.

It is a very great advantage to the amateur turner to be able to use the screw-tool with ease, for it often happens that articles are much more easily made in several pieces which can be afterwards screwed together, than when cut out of the solid piece. Box-lids, needle-case <:overs, and a thousand-and-one other articles are much better adapted to the use for which they are intended, when they screw' and unscrew, than when they simply shut.

Another great advantage of being a good screw-cutter is the ease with which chucks of all shapes and sizes may be constructed. Screwtools are sharpened by rubbing their upper surfaces on the oilstone, they seldom require grinding as the wear and tear upon them is comparatively small.

CHAPTER VII.'

ON THE CHOICE OF MATERIALS.

THE amateur having gained tolerable proficiency in the use of the lathe, will naturally next begin to look about · for raw materials,

upon which to exercise his shlll, of a more varied character than those we have already enumerated. The class ofwoods will .furnish him with an almost inexhaustible supply of all degrees of hardness and toughness, and of great variety ofcolour.

It is much to be regretted that, as a rule, amateurs are too fond of confining themselves to ivory, box, ebony, and cocoa, forgetting, or perhaps not knowing of the existence of such beautiful materials as kingwood, camwood, partridge-wood, and a host of others; They also se.em to strive as much as possible to form their wc:>rk out of a single piece of ivory or ebony, as the case may be, instead of making the different parts of woods of various colours. The· reason of this may be



sought in the fact that so few amateurs have learned the use of the screw-tool. The ambitious young workman should turn his attention se1·iously to this part of the subject, and show his friends that he can not only produce good work with his tools and lathe,,but also artistic form and pleasing combinations of colour with his head and eye. The following list of woods, with their characteristic tints and markings, will be of great help to him in this .

.Apple-tree.-This is a close-grained yellowish wood, with. a reddish tinge, of moderate toughness. It is much used for bottle-cases and screwed work, but is inferior for those purposes to pear-tree, which is closer and harder in grain. It should not be used for any very large work, as it is liable to cast. As a reddish-yellow wood, it may be used for ornamental purposes with great advantage.

Beecli.-This tree is found abundantly in most countries of Europe. The Buckingham and Sussex wood is considered the best in England. It is v,ery even in its texture, is moderately tough, and is much used for tool handles and chucks. From not being very hard, it is inferior to box for these purposes.

Beefwood.-This name is given to several woods grown in different parts of the world. The principal supply is obtained from New South Wales, where it is known as the Botany Bay oak. It is· of .a fine reddish-brown colour, with dark curly veins running through it. It is hard, close, and compact, and is greatly used for ornamental purposes.

Birch. - Birchwood is grown abundantly in Europe and North America. That from Canada is considered the best. It is softer than beech. Its colour is sometimes very beautiful, especially the variety grown in Russia, which is of a rich yellow . . Box:wood.-The finest quality of this wood i3 grown in the interior

of Turkey, and on the shores of the Black Sea. It .forms one .of the principal exports from Smyrna to this country, and is in great request for woodcengraving and other purposes. When cut across the grain, it will take the finest lines from the graver without chipping. It is hard, close, and compact, of a :fine yellow colour, and capable of receiving a . high polish. It is frequently very beautifully mottJ.ed, and should form one of the principal woods of the amateur's stock for both m~efnl a'nd ornamental purposes. For tool.handles and chucks it is invaluable. For the latter purposes, the English wood may be employed, as it is tough, and its fibre is more elastic than the Turkish variety. Its sawdust is used for cleaning jewellery.

Bullet-wood.-This is a clos~, hard, and regular wood/and would be very valuable, if it could be obtained in larger quantities, being well



adapted for the lathe. The West Indian variety is of a greenish brown that from Berbice inclining more to hazel.

Oam-wood is grown in the country surrounding Sierra Leone, and on other parts of the West African coast. It is fine, close, and hard, of a bright orange-br,own streaked with red. It is generally very beautifully marked at first, but in course of time it becomes much darker,-a remark that will apply to most woods of a very bright colour.

Oherry-tree.-A moderately hard, close-grained, reddish-brown wood, When soaked in lime-water, it takes the colour and appearance of mahogany.

Cocoa or Oocos-wood.-Thi'l wood has nothing to do either with the cocoa-nut palm or the cacao tree, from which the cocoa nib is obtained. It is hard, close, and compact, at first of a dark brown, afterwards turning almost to black. It is greatly used for very tine work, as it is less liable to chip under the tooJ. than almost any other wood.

Ooromandel wood is very hard, of a deep chocolate-brown, with black veins and streaks running through it, and resembles ebony in working and quality.

Ebony.-The intense blackness of this well-known wood has given rise to the common simile, " as black as ebony." That from Mauritius is the hardest, finest, and blackest; but it is frequently full of shakes and cracks. The East Indian variety, which is obtained from India, Ceylon, and the East Indian islands, is superior in point of soundness, but is coarser, softer, and less black, whilst the African wood from the Cape of Good Hope is the least wasteful of all, but is the most porous and worst in depth of colour. Green Ebony is the wood of an entirely different tree growing in the West Indies. It is of a greenish-brown, streaked irregularly with black, and, except in small pieces, is not much employed in ornamental turning. It is much used for making round rulers.

Holly.-This well-known wood should form the amateur's piece de resistance, whenever he requires a light-coloured material. The hest specimens are of a rich creamy white, moderately hard, close and ffoegrained. Although somewhat soft, it takes a beautiful natural polish. and is much less liable to pick up dust and dirt than horse-chestnut, sycamore, and other white woods.

Horse-chestnut is a white, close, soft, silky-grained wood, but it will not replace holly for ornamental purposes.

King-wood, . or Violet-woocl.-This magnificently-marked wood truly deserves the name of king-wood. It is pretty hard, has a fine close grain, and is beau~ifully streaked with different shades of violet. As a



adapted for the lathe. The West Indian variety is of a greenish brown that from Berbice inclining more to hazel.

Oam-wood is grown in the country surrounding Sierra Leone, and on other parts of the West African coast. It is fine, close, and hard, of a bright orange-br:own streaked with red. It is generally very beautifully marked at first, but in course of time it becomes much darker,-a remark that will apply to most woods of a very bright colour.

Oherry-tree.-A moderately hard, close-grained, reddish-brown wood, When soaked in lime-water, it takes the colour and appearance of mahogany.

Cocoa or Cocos-wood.-Thi<> wood has nothing to do either with the cocoa-nut palm or the cacao tree, from which the cocoa nib is obtained. It is hard, close, and compact, at first of a dark brown, afterwards turning almost to black. It is greatly used for very tine work, as it is less liable to chip under the tooJ. than almost any other wood.

Ooromandel wood is very hard, of a deep chocolate-brown, with black veins and streaks running through it, and resembles ebony in working and quality.

Ebony.-The intense blackness of this well-known wood has given rise to the common simile, " as black as ebony." That from Mauritius is the hardest, finest, and blackest; but it is frequently full of shakes and cracks. The East Indian variety, which is obtained from India, Ceylon, and the East Indian islands, is superior in point of soundness, but is coarser, softer, and less black, whilst the African wood from the Cape of Good Hope is the least wasteful of all, but is the most porous and worst in depth of colour. Green Ebony is the wood of an entirely different tree growing in the West Indies. It is of a greenish-brown, streaked irregularly with black, and, except in small pieces, is not much employed in ornamental turning. It is much used for making round rulers.

Holly.-This well-known wood should form the amateur's piece de resistance, whenever he requires a light-coloured material. The best specimens are of a rich creamy white, moderately hard, close and :linegrained. Although somewhat soft, it takes a beautiful natural polish. and is much less liable to pick up dust and dirt than horse-chestnut, sycamore, and other white woods.

Horse-chestnut is a white, close, soft, silky-grained wood, but it will not replace holly for ornamental purposes.

King-wood,. or Violet-wood.-This magnificently-marked wood truly deserves the name of king-wood. It is pretty hard, has a fine close grain, and is beau~ifully streaked with different shades of violet. As a


TllE PRINCIPLES AND PRACTICE OF PLAIN TURNING. 7 53

means of introducing colour into ornamental work, it is perhaps unequalled.

J(iabopca-wood, or Amboyna-v,ood, as it is often termed, is another ornamental wood, which for beauty of colour may vie with king-wood. It varies from orange to reddish-brown, and is beautifully marked with

. curly streaks. Few other woods exceed it in beauty, more especially when large flat surfaces are exposed to view.

Pear-tree is similar to apple-tree, but is somewhat browner, tougher, and less liable to cast. It is much used for printing-bloc1rn, as it cutfl with great facility in all directions of the grain.

Piirple-wood is said to be a variety of king-wood. When worked it is of a dark grey, which gradually turns to a deep purple.

Partridge-wood is another material that is highly esteemed for ornamental purposes. It is close, .heavy, and straight-grained. The markings are brown of various shades, streaked with grey; and some specimens bear a singular resemblance to the feathers of the bird from which it is named.

Ligniiin Vita> is a hard, heavy wood, used greatly for skittle-balls, tops, rollers, sheaves for ships' blocks, and other coarse wqrk of a similar character. It is of a dull greenish-brown in colour, and is too irregular in tint .and grain to be used in ornamental turning.

Maliogciny is too familiar to need description. The Spanish variety is .more close-grained and hard than that from Honduras, besides being generally beautifully marked.

~lfaple.--The American variety of this wood-generally called bird'seye maple-forms an excellent material for large 'vorks. It is too well known to need description.

Quassia-wood is sometimes turned into cups, which give out the bitter principle of the wood when water is poured into them. It is a soft wood, and destitute of ornamental qualities.

Red Sanders-wood is hard and heavy. It has a fine red colour at first, but afterwards turns brown.

Rosetta-wood is of a bright-red orange, streaked with ·dark veins. At first it is very beautiful, but gradually becomes darker.

Rose-wood is hard and close in most specimens ; there are many logs, however, which are comparatively soft. It is not an ea::iy wood to turn smooth, owing to the dark portions being harder than the r~st. It is used both for furniture and turned work in large quantities. The best quality comes from Rio de Janeiro. It contains a fragrant oil, which is exceedingly inflammable, a small splinter of the wood burning like a candle.

3 c


TllE PRINCIPLES AND PRACTICE OF PLAIN TURNING. 753

means of introducing colour into ornamental work, it is perhaps unequalled.

J(iabopca-wood, or Amboyna-vJood, as it is often termed, is another ornamental wood, which for beauty of colour may vie with king-wood. It varies from orange to reddish-brown, and is beautifully marked with

. curly .streaks. Few other woods exceed it in beauty, more especially when large flat surfaces are exposed to view.

Pear-tree is similar to apple-tree, but is somewhat browner, touglrnr, and less liable to cast. It is much used for printing-blocks, as it cutR with great facility in all directions of the grain.

Piirple-wood is said to be a variety of king-wood. When worked it is of a dark grey, which gradually turns to a deep purple.

Partridge-wood is another material that is highly esteemed for ornamental purposes. It is close, .heavy, and straight-grained. The markings are brown of various shades, streaked with grey; and some specimens bear a singular resemblance to the feathers of the bird from which it is named.

Ligniiin Vitro is a hard, heavy wood, used greatly for skittle-balls, tops, rollers, sheaves for ships' blocks, and other coarse wqrk of a similar character. It is of a dull greenish-brown in colour, and is too irregular in tint and grain to be used in ornamental turning.

Maliogciny is too familiar to need description. The Spanish variety is .more close-grained and hard than that from Honduras, besides being generally beautifully marked.

~lfaple.--The American variety of this wood-generally called bird'seye maple-forms an excellent material for large 'vorks. It is too well known to need description.

Quassia-wood is sometimes turned into cups, which give out the bitter principle of the wood when water is poured into them. It is a soft wood, and destitute of ornamental qualities.

Red Sanders-wood is hard and heavy. It has a fine red colour at first, but afterwards turns brown.

Rosetta-wood is of a bright-red orange, streaked with ·dark veins. At first it is very beautiful, but gradually becomes darker.

Rose-wood is hard and close in most specimens ; there are many logs, however, which are comparatively soft. It is not an easy wood to turn smooth, owing to the dark portions being harder than the r~st. It is used both for furniture and turned work in large quantities. The best quality comes from Rio de Janeiro. It contains a fragrant oil, which is exceedingly inflammable, a small splinter of the wood burning like a candle.

3 c


754 THE LATHE, .AND HOW TO USE IT j Olt,

Sanrlal-woocl is the product of a myrtle-like tree growing in Malabar It, is a yellow wood, somewhat resembling box in appearance, but is much softer. It ought to be a great favourite'with the amateur, on account of the delicious perfume it constantly exhales.

Satin-wood is of a fine yellow colour, close-grained and moderately hard. It turns well in the lathe, with care. Some specimens are beautifully mottled.

Snake-wood.-This wood is of a bright brown colour, splashed with darker brown or black spots; whence its name. It is rather scarce and dear in this country.

Tulip-wood is a favourite ornamental material with the cabinet-maker and turner. It is of a light reddish-brown, with blood-red streaks. It is difficult to work in the lathe, being splintery and apt to chip. It is best adapted to work with broad surfaces.

Yacca-wood is pale brown, streaked with hazel. Zebra- or Pigeori-wood is orange-brown, streaked with dark brown. It

is very handsome, and not difficult to work. Besides the woods above mentioned, the turner uses ivory, bone,

horn, and shells and nuts; of various kinds. In point of beauty, the chief of these is undoubtedly ivory. In all

ages, and in all countries where true art has flourished, we . find this beautiful substance extensively used.

Ivory is the hard substance forming the tusks of the male elephant, walrus, and sea-horse. They are hollow at the root, and vary in size according to the age of the animal. The finest quality is imported in large quantities from the west and east coasts of Africa. The East Indian ivory, the product of Ceylon and the continent of India, is of inferior quality, being. less close in texture, and more liable to turn brown than that from Africa.

Horn and bo11e being rarely used by the amateur, need no particular description.

The betel-nut is much used for small work, such as the knobs of parasols, the covers of small boxes, and similar articles. It is the pro_ duct of the Areca catecliu, a graceful palm which grows extensively in the tropics. The main body of the nut is of a greyish-white, covered with bright brown markings, which form a pretty network over the whole surface. The betel-nut is rather softer than ivory, and about the size of a small walnut.

The Coquilla-nut is the fruit of the Attaleci funifera, a tree growing principally in Brazil. It contains two seeds, which taste something like cocoa-nut. It is of bright yellowish-brown, streaked with lighter and


754 THE LATHE, .A.ND HOW TO USE IT j Oit,

Sandal-wood is the product of a myrtle-like tree growing in Malabar It, is a yellow wood, somewhat resembling box in appearance, but is much softer. It ought to be a great favourite ·with the amateur, on account of the delicious perfume it constantly exhales.

Satin-wood is of a fine yellow colour, close-grained and moderately hard. It turns well in the lathe, with care. Some specimens are beautifully mottled.

Snake-wood.-This wood is of a bright brown colour, splashed with darker brown or black spots; whence its name. It is rather scarce and dear in this country.

Tulip-wood is a favourite ornamental material with the cabinet-maker and turner. It is of a light reddish-brown, with blood-red streaks. It is difficult to work in the lathe, being splintery and apt to chip. It is best adapted to work with broad surfaces.

Yacca-wood is pale brown, streaked with hazel. Zebra- or Pigeori-wood is orange-brown, streaked with dark brown. It

is very handsome, and not difficult to work. Besides the woods above mentioned, the turner uses ivory, bone,

horn, and shells and nuts; of various kinds. In point of beauty, the chief of these is undoubtedly ivory. In all

ages, and in all countries where true art has flourished, we . find this beautiful substance extensively used.

Ivory is the hard substance forming the tusks of the male elephant, walrus, and sea-horse. They are hollow at the root, and vary in size according to the age of the animal. The finest quality is imported in large quantities from the west and east coasts of Africa. The East Indian ivory, the product of Ceylon and the continent of India, is of inferior quality, being. less close in texture, and more liable to turn brown than that from Africa.

Horn and bo11e being rarely used by the amateur, need no particular description.

The betel-nut is much used for small work, such as the knobs of parasols, the covers of small boxes, and similar articles. It is the pro_ duct of the Areca catecliu, a graceful palm which grows extensively in the tropics. The main body of the nut is of a greyish-white, covered with bright brown markings, which form a pretty network over the whole surface. The betel-nut is rather softer than ivory, and about the size of a small walnut.

The Coquilla-nut is the fruit of the Attalect funifera, a tree growing principally in Brazil. It contains two seeds, which taste something like cocoa-nut. It is of bright yellowish-brown, streaked with lighter and



darker markings. It bears a high polish, and, being hard and tough, forms excellent screws.

The Oorosos, or Vegetable Ivory nuts, are the product of the Phyte[ephas macroca;rpa, a native of Central America. They are of an irregular globular shape, and contain a hole in the Il_liddle. They are whiter than ivory, but in course of time they become dusky in hue. They are hard and tough, screw well, and take a high polish.

Ivory and the nuts generally should be finished with a rag covered with whiting. A finishing touch with an infinitesimal portion of oil may be given ; but in the case of ivory too much is liable to turn it yellow.

THE END OF THE LATHE, AND HOW TO USE IT.

3 c 2



darker markings. It bears a high polish, and, being hard and tough, forms excellent screws.

The Oorosos, or Vegetable Ivory nuts, are the product of the Phyte[ephas macrocaJrpa, a native of Central America. They are of an irregular globular shape, and contain a hole in the 11!-iddle. They are whiter than ivory, but in course of time they become dusky in hue. They are hard and tough, screw well, and take a high polish.

Ivory and the nuts generally should be finished with a rag covered with whiting. A finishing touch with an infinitesimal portion of oil may be given ; but in the case of ivory too much is liable to turn it yellow.

THE END OF THE LATHE, AND HOW TO USE IT.

3 c 2


Documents

Temple Thorold Turning 1867